Website report

NIH

nih.gov ↗·🇺🇸 United States · Government

Measured

Global rank#116
GradeA

Your result

No broken links found in this sample.

Link health
100.00/100

Healthy links in the sample

Quality checklist
76.94/100

Scored technical checks

Broken links
0

Confirmed in sample

57 links verified · 143 unknown · 20 selected source pages · 29% of selected destinations verified. Sample only. Unknown links are not counted as broken.

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What to fix first

View all priorities →

Includes issues from the extended diagnostic report.

  1. Main heading

    Add a descriptive H1 identifying the main topic.

  2. Heading hierarchy

    Nest headings logically without skipping a level, starting with H1.

  3. Image dimensions declared

    Declare width and height attributes (or an inline aspect-ratio style) on every visible <img> so the browser reserves space before the image loads. Reference: web.dev / Lighthouse "image elements have explicit width and height" (layout shift).

Fix with your coding assistant

Copy a ready-to-use prompt with the issues and affected URLs.

Your path to S-Tier

Not yet S-Tier

Healthy links, every scored requirement passed, and complete evidence in the selected sample.

  • Revalidate the badge with a new scan (valid for 30 days).
  • Pass all scored quality requirements across the five categories.
  • Verify every required check and selected destination; incomplete or retained evidence cannot unlock the badge.
Badge requirements
How this result qualifies

Verified internal navigation

At least 10 internal destinations were verified. Unknown items do not disqualify the site; confirmed checklist failures reduce quality.

100.00/100 link health · 76.94/100 quality · 57 internal destinations

New comparison baseline. A change in coverage is not a verified improvement.

The diagnostic report below may cover additional pages and external links. Only the stored competitive sample determines the ranking. At least 10 verified internal links are required; unavailable checklist items do not exclude a site. How scoring works

Explore issues & evidenceConfirmed issues, suggested fixes and the evidence behind them.
0 diagnostic broken links52 pages readExtended evidence may include links outside the badge sample.

Broken links & sources

Latest competitive sample and evidence · 76.94/100 quality

At least 10 internal destinations were verified. Unknown items do not disqualify the site; confirmed checklist failures reduce quality. Each item is evaluated independently; unavailable readings do not veto the result.

20 selected source URLs · 200 internal destinations. 57 evaluated · 143 unknown · 0 using previous evidence. The expanded diagnostic report follows below.

Some checklist evidence is unavailable: Page title, Distinct page titles, Meta description, Self-referencing canonical, Main heading, Heading hierarchy, Main landmark, Mobile viewport, Image dimensions declared, Structured data syntax, Document language, Image alternatives declared, Form controls named, Buttons named, Links named, Descriptive link text, Open Graph title, Open Graph description, Open Graph type, Open Graph URL, Open Graph image URL, Open Graph image description, Social card type, HTTPS page, No insecure embedded resources. 0 check(s) use previous evidence, for at most eight days from their last reliable reading. Other unknown observations have no scoring vote.

SEO
100.00/100
Accessibility
83.33/100
Structure
33.33/100
Sharing
77.78/100
Security
100.00/100
Selected pages
  • https://www.nih.gov/
  • https://www.nih.gov/about-nih
  • https://www.nih.gov/about-nih/contact-us
  • https://www.nih.gov/about-nih/frequently-asked-questions
  • https://www.nih.gov/about-nih/get-involved-nih
  • https://www.nih.gov/about-nih/impact-nih-research
  • https://www.nih.gov/about-nih/mission-goals
  • https://www.nih.gov/about-nih/nih-almanac
  • https://www.nih.gov/about-nih/nih-director
  • https://www.nih.gov/about-nih/nih-turning-discovery-into-health
  • https://www.nih.gov/about-nih/organization
  • https://www.nih.gov/about-nih/science-health-public-trust
  • https://www.nih.gov/about-nih/visitor-information
  • https://www.nih.gov/accessibility
  • https://www.nih.gov/disclaimers
  • https://www.nih.gov/grants-funding
  • https://www.nih.gov/health-information
  • https://www.nih.gov/health-information/nih-clinical-research-trials-you
  • https://www.nih.gov/health-information/your-healthiest-self-wellness-toolkits
  • https://www.nih.gov/institutes-nih
Internal link verdicts and weights
  • ok · weight 6 · https://calendar.nih.gov/
  • unverifiable · weight 6 · https://eeo.nih.gov/no-fear-act
  • ok · weight 6 · https://grants.nih.gov/
  • ok · weight 6 · https://grants.nih.gov/funding
  • ok · weight 6 · https://grants.nih.gov/funding/funding-categories/contracts
  • ok · weight 6 · https://grants.nih.gov/funding/funding-categories/lrp
  • ok · weight 6 · https://grants.nih.gov/grants-process/submit/submission-policies/standard-due-dates
  • ok · weight 6 · https://grants.nih.gov/grants-process/write-application/how-to-apply-application-guide
  • ok · weight 6 · https://grants.nih.gov/new-to-nih
  • ok · weight 6 · https://grants.nih.gov/news-events/nih-extramural-nexus-news
  • ok · weight 6 · https://grants.nih.gov/policy-and-compliance
  • unverifiable · weight 6 · https://hr.nih.gov/jobs
  • unverifiable · weight 6 · https://newsinhealth.nih.gov/
  • unverifiable · weight 6 · https://salud.nih.gov/
  • ok · weight 6 · https://science.education.nih.gov/
  • ok · weight 6 · https://www.nih.gov/
  • unverifiable · weight 6 · https://www.nih.gov/about-nih
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/contact-us
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/frequently-asked-questions
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/get-involved-nih
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/impact-nih-research
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/mission-goals
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/nih-almanac
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/nih-director
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/nih-turning-discovery-into-health
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/organization
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/science-health-public-trust
  • unverifiable · weight 6 · https://www.nih.gov/about-nih/visitor-information
  • unverifiable · weight 6 · https://www.nih.gov/accessibility
  • unverifiable · weight 6 · https://www.nih.gov/disclaimers
  • unverifiable · weight 6 · https://www.nih.gov/grants-funding
  • unverifiable · weight 6 · https://www.nih.gov/health-information
  • unverifiable · weight 6 · https://www.nih.gov/health-information/nih-clinical-research-trials-you
  • unverifiable · weight 6 · https://www.nih.gov/health-information/your-healthiest-self-wellness-toolkits
  • unverifiable · weight 6 · https://www.nih.gov/institutes-nih
  • unverifiable · weight 6 · https://www.nih.gov/institutes-nih/directors-nih-institutes-centers
  • unverifiable · weight 6 · https://www.nih.gov/institutes-nih/list-institutes-centers
  • unverifiable · weight 6 · https://www.nih.gov/institutes-nih/nih-office-director
  • unverifiable · weight 6 · https://www.nih.gov/institutes-nih/nih-office-director/office-communications-public-liaison/freedom-information-act-office
  • unverifiable · weight 6 · https://www.nih.gov/institutes-nih/office-communications-public-liaison/clear-communication/talking-your-doctor-or-health-care-provider
  • unverifiable · weight 6 · https://www.nih.gov/news-events
  • unverifiable · weight 6 · https://www.nih.gov/news-events/images-b-roll
  • unverifiable · weight 6 · https://www.nih.gov/news-events/media-inquiries
  • unverifiable · weight 6 · https://www.nih.gov/news-events/news-releases
  • unverifiable · weight 6 · https://www.nih.gov/news-events/nih-news-publications
  • unverifiable · weight 6 · https://www.nih.gov/news-events/nih-social-media
  • unverifiable · weight 6 · https://www.nih.gov/news-releases/feed.xml
  • unverifiable · weight 6 · https://www.nih.gov/nih-website-archives
  • unverifiable · weight 6 · https://www.nih.gov/nondiscrimination-notice
  • unverifiable · weight 6 · https://www.nih.gov/press-room
  • unverifiable · weight 6 · https://www.nih.gov/privacy-policy
  • unverifiable · weight 6 · https://www.nih.gov/research-training
  • unverifiable · weight 6 · https://www.nih.gov/research-training/clinical-research-resources
  • unverifiable · weight 6 · https://www.nih.gov/research-training/lasker-clinical-research-scholars
  • unverifiable · weight 6 · https://www.nih.gov/research-training/library-resources
  • unverifiable · weight 6 · https://www.nih.gov/research-training/medical-research-initiatives
  • unverifiable · weight 6 · https://www.nih.gov/research-training/research-nih-labs-clinics
  • unverifiable · weight 6 · https://www.nih.gov/research-training/research-resources
  • unverifiable · weight 6 · https://www.nih.gov/research-training/safety-regulation-guidance
  • unverifiable · weight 6 · https://www.nih.gov/research-training/science-highlights
  • unverifiable · weight 6 · https://www.nih.gov/research-training/training-opportunities
  • unverifiable · weight 6 · https://www.nih.gov/virtual-tour
  • ok · weight 4 · https://grants.nih.gov/grants/guide/notice-files/NOT-DE-26-015.html
  • ok · weight 4 · https://irp.nih.gov/
  • unverifiable · weight 4 · https://researchfestival.nih.gov/
  • unverifiable · weight 4 · https://www.jobs.nih.gov/
  • ok · weight 4 · https://www.niaaa.nih.gov/publications/brochures-and-fact-sheets/understanding-fetal-alcohol-spectrum-disorders
  • unverifiable · weight 4 · https://www.nih.gov/about-nih/what-we-do/impact-nih-research
  • unverifiable · weight 4 · https://www.nih.gov/about-nih/who-we-are/nih-director
  • unverifiable · weight 4 · https://www.nih.gov/challenges/nourish-autoimmunity-digital-health-challenge
  • unverifiable · weight 4 · https://www.nih.gov/heal
  • unverifiable · weight 4 · https://www.nih.gov/research-training/accelerating-medicines-partnership-amp
  • unverifiable · weight 4 · https://www.nih.gov/web-modernization
  • unverifiable · weight 2 · http://report.nih.gov/
  • ok · weight 2 · https://dpcpsi.nih.gov/oepr/nih-information-quality
  • ok · weight 2 · https://dpcpsi.nih.gov/thro
  • unverifiable · weight 2 · https://go.nih.gov/CoGxmos
  • unverifiable · weight 2 · https://go.nih.gov/idUS6tA
  • unverifiable · weight 2 · https://go.nih.gov/vqNp7dg
  • unverifiable · weight 2 · https://go.nih.gov/xYO8v1i
  • ok · weight 2 · https://grants.nih.gov/funding/funding-categories
  • ok · weight 2 · https://grants.nih.gov/funding/funding-categories/research-training-and-career-development
  • unverifiable · weight 2 · https://history.nih.gov/
  • ok · weight 2 · https://irp.nih.gov/catalyst
  • unverifiable · weight 2 · https://list.nih.gov/cgi-bin/wa.exe?A0=nihhealthinformation
  • ok · weight 2 · https://ncats.nih.gov/
  • ok · weight 2 · https://nccih.nih.gov/
  • ok · weight 2 · https://nccih.nih.gov/research/statistics
  • ok · weight 2 · https://nei.nih.gov/
  • unverifiable · weight 2 · https://newsinhealth.nih.gov/2023/01/your-bodys-disease-defenses
  • unverifiable · weight 2 · https://newsinhealth.nih.gov/2023/07/delivering-safer-pregnancies
  • unverifiable · weight 2 · https://newsinhealth.nih.gov/2023/08/breaking-down-food
  • unverifiable · weight 2 · https://newsinhealth.nih.gov/2023/11/be-citizen-scientist
  • unverifiable · weight 2 · https://newsinhealth.nih.gov/2023/11/sore-scratchy-throat
  • ok · weight 2 · https://nida.nih.gov/
  • unverifiable · weight 2 · https://nih.gov/about-nih/selected-nih-education-awareness-campaigns
  • unverifiable · weight 2 · https://nihrecord.nih.gov/
  • ok · weight 2 · https://oamp.od.nih.gov/
  • unverifiable · weight 2 · https://officeofbudget.od.nih.gov/
  • ok · weight 2 · https://ors.od.nih.gov/maps/Pages/default.aspx
  • ok · weight 2 · https://ors.od.nih.gov/pes/dats/Pages/index.aspx
  • ok · weight 2 · https://report.nih.gov/funding/categorical-spending/rcdc-process
  • unverifiable · weight 2 · https://salud.nih.gov/recursos-de-salud/herramientas-de-bienestar
  • unverifiable · weight 2 · https://salud.nih.gov/sobre-los-nih/contactenos/consultas-ideas-comentarios-generales
  • ok · weight 2 · https://search.nih.gov/search?utf8=%E2%9C%93&affiliate=hip&query=cancer&commit=
  • ok · weight 2 · https://search.nih.gov/search?utf8=%E2%9C%93&affiliate=hip&query=diabetes&commit=
  • ok · weight 2 · https://search.nih.gov/search?utf8=%E2%9C%93&affiliate=hip&query=fitness&commit=
  • ok · weight 2 · https://search.nih.gov/search?utf8=%E2%9C%93&affiliate=hip&query=healthy%20eating&commit=
  • ok · weight 2 · https://search.nih.gov/search?utf8=%E2%9C%93&affiliate=hip&query=heart%20disease&commit=
  • ok · weight 2 · https://search.nih.gov/search?utf8=%E2%9C%93&affiliate=hip&query=mental%20health&commit=
  • ok · weight 2 · https://search.nih.gov/search?utf8=%E2%9C%93&affiliate=hip&query=sleep&commit=
  • ok · weight 2 · https://search.nih.gov/search?utf8=%E2%9C%93&affiliate=hip&query=stroke&commit=
  • ok · weight 2 · https://security.nih.gov/Pages/Home.aspx
  • ok · weight 2 · https://security.nih.gov/visitors/Pages/default.aspx
  • ok · weight 2 · https://seed.nih.gov/
  • ok · weight 2 · https://stemcells.nih.gov/
  • unverifiable · weight 2 · https://www.cc.nih.gov/
  • unverifiable · weight 2 · https://www.cc.nih.gov/participate
  • unverifiable · weight 2 · https://www.cc.nih.gov/participate/studies
  • unverifiable · weight 2 · https://www.cc.nih.gov/recruit/volunteers
  • unverifiable · weight 2 · https://www.cc.nih.gov/volunteers/opportunities
  • ok · weight 2 · https://www.cit.nih.gov/
  • ok · weight 2 · https://www.csr.nih.gov/
  • ok · weight 2 · https://www.fic.nih.gov/
  • ok · weight 2 · https://www.nccih.nih.gov/
  • ok · weight 2 · https://www.nei.nih.gov/about/education-and-outreach/eye-health-data-and-statistics
  • ok · weight 2 · https://www.nhlbi.nih.gov/
  • unverifiable · weight 2 · https://www.nia.nih.gov/
  • ok · weight 2 · https://www.niaaa.nih.gov/
  • unverifiable · weight 2 · https://www.niaid.nih.gov/
  • unverifiable · weight 2 · https://www.niaid.nih.gov/research/emerging-infectious-disease-research-and-countermeasures
  • unverifiable · weight 2 · https://www.niams.nih.gov/
  • unverifiable · weight 2 · https://www.nibib.nih.gov/
  • ok · weight 2 · https://www.nichd.nih.gov/
  • ok · weight 2 · https://www.nidcd.nih.gov/
  • ok · weight 2 · https://www.nidcd.nih.gov/health/statistics
  • ok · weight 2 · https://www.nidcr.nih.gov/
  • ok · weight 2 · https://www.nidcr.nih.gov/DataStatistics/
  • ok · weight 2 · https://www.niddk.nih.gov/
  • ok · weight 2 · https://www.niddk.nih.gov/health-information/health-statistics
  • ok · weight 2 · https://www.niehs.nih.gov/
  • ok · weight 2 · https://www.nigms.nih.gov/
  • unverifiable · weight 2 · https://www.nigms.nih.gov/Research/DRCB/sepa/Pages/default.aspx
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/ask-nih
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/budget
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/contact-us/ask-nih
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/history
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/impact-nih-research/improving-health
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/impact-nih-research/our-stories
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/impact-nih-research/revolutionizing-science
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/impact-nih-research/serving-society
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/impact-nih-research/serving-society/societal-benefits-improved-health
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/national-institutes-hope-help-us-help-you
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-almanac/about-nih-almanac
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-almanac/appropriations-section-1
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-almanac/lasker-awards
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-almanac/leadership
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-almanac/nih-organization
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-almanac/nobel-laureates
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-almanac/photo-galleries
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-almanac/timelines
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-director/advisory-groups
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-director/directors-seminar-series
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-director/nih-scientific-freedom-lecture-series
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-director/previous-nih-directors
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-director/statements
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-leadership
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-research-planning
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-turning-discovery-into-health/future-biomedicine
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-turning-discovery-into-health/healthy-mind
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-turning-discovery-into-health/looking-forward
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-turning-discovery-into-health/our-biggest-health-challenges
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-turning-discovery-into-health/promise-precision-medicine
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-turning-discovery-into-health/research-healthy-living
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/nih-turning-discovery-into-health/transformative-technologies
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/organization/budget
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/organization/history
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/organization/nih-leadership
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/organization/organization-charts-functional-statements
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/science-health-public-trust/checklist-communicating-science-health-research-public
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/science-health-public-trust/perspectives/challenges-understanding-communicating-health-risks
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/science-health-public-trust/perspectives/explaining-how-research-works
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/science-health-public-trust/perspectives/understanding-clinical-studies
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/science-health-public-trust/tools
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/selected-nih-education-awareness-campaigns
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/visitor-information/getting-nih
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/visitor-information/nih-special-events-branch-tours
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/visitor-information/nih-visitor-center-nobel-laureate-exhibit-hall
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/voices-nih-community
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/what-we-do/mission-goals
  • unverifiable · weight 2 · https://www.nih.gov/about-nih/who-we-are/nih-director/articles/celebration-science-nih
  • unverifiable · weight 2 · https://www.nih.gov/health-information/health-info-lines
  • unverifiable · weight 2 · https://www.nih.gov/health-information/nih-clinical-research-trials-you/basics
  • unverifiable · weight 2 · https://www.nih.gov/health-information/nih-clinical-research-trials-you/educational-resources
  • unverifiable · weight 2 · https://www.nih.gov/health-information/nih-clinical-research-trials-you/finding-clinical-trial
  • unverifiable · weight 2 · https://www.nih.gov/health-information/nih-clinical-research-trials-you/glossary-common-terms
  • unverifiable · weight 2 · https://www.nih.gov/health-information/nih-clinical-research-trials-you/health-care-providers
  • unverifiable · weight 2 · https://www.nih.gov/health-information/nih-clinical-research-trials-you/highlights
  • unverifiable · weight 2 · https://www.nih.gov/health-information/nih-clinical-research-trials-you/if-you-have-question
  • unverifiable · weight 2 · https://www.nih.gov/health-information/nih-clinical-research-trials-you/list-registries
Scoring checks
  • Page title: passed · 1/1 applicable observations

    https://www.nih.gov/: National Institutes of Health (NIH) |

  • Meta description: passed · 1/1 applicable observations

    https://www.nih.gov/: Official website of the National Institutes of Health (NIH). NIH is one of the world's foremost medical research centers. An agency of the U.S. Department of Health and Human Services, the NIH is the Federal focal point for health and medical research. The NIH

  • Self-referencing canonical: passed · 1/1 applicable observations

    https://www.nih.gov/: https://www.nih.gov/

  • Main heading: failed · 0/1 applicable observations

    https://www.nih.gov/: 0 H1 element(s)

  • Heading hierarchy: failed · 0/1 applicable observations

    https://www.nih.gov/: 1 skipped heading level(s)

  • Main landmark: passed · 1/1 applicable observations

    https://www.nih.gov/: 1 main landmarks

  • Mobile viewport: passed · 1/1 applicable observations

    https://www.nih.gov/: width=device-width, initial-scale=1.0

  • Image dimensions declared: failed · 0/1 applicable observations

    https://www.nih.gov/: 16 of 16 images lack width/height attributes or an aspect-ratio style

  • Structured data syntax: failed · 0/1 applicable observations

    https://www.nih.gov/: 0 of 0 blocks have valid JSON-LD structure

  • Document language: passed · 1/1 applicable observations

    https://www.nih.gov/: en

  • Image alternatives declared: passed · 1/1 applicable observations

    https://www.nih.gov/: 0 of 16 images lack an alt attribute

  • Form controls named: passed · 1/1 applicable observations

    https://www.nih.gov/: 0 of 1 controls have no HTML label

  • Buttons named: passed · 1/1 applicable observations

    https://www.nih.gov/: 0 of 10 buttons have no HTML name

  • Links named: passed · 1/1 applicable observations

    https://www.nih.gov/: 0 of 49 links have no HTML name

  • Descriptive link text: failed · 0/1 applicable observations

    https://www.nih.gov/: 1 of 49 links use generic text: "learn more"

  • Open Graph title: failed · 0/1 applicable observations

    https://www.nih.gov/: No og:title

  • Open Graph description: passed · 1/1 applicable observations

    https://www.nih.gov/: Official website of the National Institutes of Health (NIH). NIH is one of the world's foremost medical research centers. An agency of the U.S. Department of Health and Human Services, the NIH is the Federal focal point for health and medical research. The NIH

  • Open Graph type: passed · 1/1 applicable observations

    https://www.nih.gov/: Article

  • Open Graph URL: passed · 1/1 applicable observations

    https://www.nih.gov/: https://www.nih.gov/node

  • Open Graph image URL: passed · 1/1 applicable observations

    https://www.nih.gov/: https://www.nih.gov/sites/default/files/styles/thumbnail_large/public/2025-01/thumbnail-generic.png

  • Open Graph image description: failed · 0/1 applicable observations

    https://www.nih.gov/: No sharing image description

  • Social card type: passed · 1/1 applicable observations

    https://www.nih.gov/: summary

  • HTTPS page: passed · 1/1 applicable observations

    https://www.nih.gov/: https://www.nih.gov/

  • No insecure embedded resources: passed · 1/1 applicable observations

    https://www.nih.gov/: 0 HTTP embedded resource URL(s)

  • Homepage favicon available: passed · 1/1 applicable observations

    https://www.nih.gov/themes/custom/nih2_uswds/assets/img/favicons/custom/favicon-192x192.png: HTTP 200; image/png

  • Homepage sharing image available: passed · 1/1 applicable observations

    https://www.nih.gov/sites/default/files/styles/thumbnail_large/public/2025-01/thumbnail-generic.png: HTTP 200; image/png

  • Root sitemap available: passed · 1/1 applicable observations

    https://www.nih.gov/sitemap.xml: HTTP 200; sitemap root found

  • Rendered color contrast: unverified · 0/1 applicable observations

    https://www.nih.gov/: Requires a browser or human assessment; excluded from points.

  • Keyboard and focus behavior: unverified · 0/1 applicable observations

    https://www.nih.gov/: Requires a browser or human assessment; excluded from points.

  • HSTS declared: passed · 1/1 applicable observations

    https://www.nih.gov/: Strict-Transport-Security: max-age=31536000; includeSubDomains; preload

  • Content Security Policy declared: passed · 1/1 applicable observations

    https://www.nih.gov/: Content-Security-Policy: default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval' *.nih.gov *.googleapis.com *.govdelivery.com *.hatchbuck.com *.youtube.com *.here.com search.usa.gov *.jquery.com *.crazyegg.com *.addthis.com *.addthisedge.com cdn.js

Sample reference: 0c6a9d48b9bd8fcc78f4485f3fb22d452dee7a81605e3cb77b72f9ba01182848

No confirmed broken links in this sample. Unverified URLs are not evidence of healthy links.

Diagnostic checklist

25 passed · 7 need work · 3 not verified. Open a check for the evidence and suggested fix.

SEO
100.00
Accessibility
83.33
Structure
33.33
Sharing
77.78
Security
100.00
AI access
100.00
Performance
100.00
HTTP response measurement

123 ms median to homepage response headers. Measurements: 261, 123, 121 ms.

Same crawler, three sequential requests, DNS and TLS included. Timing is diagnostic only and never decides a position. This is server/network response, not browser loading or Core Web Vitals.

Static checks inspect crawler-visible HTML; they do not certify accessibility or code quality.

SEO0 to improve
Page titlePassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Give each page a descriptive, non-empty <title>.

Distinct page titlesNot applicable

No applicable elements found. Informational; excluded from points.

How to improve: Use a title that describes the purpose of this page rather than repeating the same title across URLs.

Meta descriptionPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Add a non-empty meta name="description" that summarizes this page.

  • https://www.nih.gov/Official website of the National Institutes of Health (NIH). NIH is one of the world's foremost medical research centers. An agency of the U.S. Department of Health and Human Services, the NIH is the Federal focal point for health and medical research. The NIH
Self-referencing canonicalPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Declare exactly one <link rel="canonical"> whose absolute URL is this page's own final URL (same scheme, host, path and query; only a trailing slash or fragment may differ). Cross-URL canonicals belong on duplicate pages, not on the indexable page itself. Reference: Google Search Central, canonicalization.

Root sitemap availablePassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Publish a sitemap URL set or index at /sitemap.xml. This checks its root, not every listed URL.

Accessibility1 to improve
Document languagePassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Declare a valid language tag on the html element, such as en or pt-BR.

Image alternatives declaredPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Add alt text to informative images. Use alt="" for decorative images. This check does not judge text quality.

Form controls namedPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Associate a label with each visible form control, or provide a non-empty aria-label / valid aria-labelledby.

Buttons namedPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Give every button visible text or an accessible name, including icon-only buttons.

Descriptive link textNeeds work

0/1 applicable observations passed. 0.00/1 checklist weight earned.

How to improve: Replace generic link text such as "click here", "read more" or "saiba mais" with text (or an aria-label) that describes the destination. Reference: WCAG 2.4.4 Link Purpose (In Context).

Rendered color contrastNot verified

0/1 applicable observations passed. Informational; excluded from points.

How to improve: Check foreground/background contrast in the rendered page.

Keyboard and focus behaviorNot verified

0/1 applicable observations passed. Informational; excluded from points.

How to improve: Test every interactive control with a keyboard and inspect focus visibility.

Structure4 to improve
Main headingNeeds work

0/1 applicable observations passed. 0.00/1 checklist weight earned.

How to improve: Add a descriptive H1 identifying the main topic.

Heading hierarchyNeeds work

0/1 applicable observations passed. 0.00/1 checklist weight earned.

How to improve: Nest headings logically without skipping a level, starting with H1.

Main landmarkPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Mark the main content with one <main> or role="main" landmark.

Mobile viewportPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Add meta name="viewport" with width=device-width and do not disable user zoom.

Image dimensions declaredNeeds work

0/1 applicable observations passed. 0.00/1 checklist weight earned.

How to improve: Declare width and height attributes (or an inline aspect-ratio style) on every visible <img> so the browser reserves space before the image loads. Reference: web.dev / Lighthouse "image elements have explicit width and height" (layout shift).

Structured data syntaxNeeds work

0/1 applicable observations passed. 0.00/1 checklist weight earned.

How to improve: Provide JSON-LD with @context and @type (or a typed @graph). Match the markup to the visible content; syntax alone does not validate its meaning. Reference: schema.org and Google structured data guidelines.

Sharing2 to improve
Open Graph titleNeeds work

0/1 applicable observations passed. 0.00/1 checklist weight earned.

How to improve: Provide a non-empty og:title meta property.

Open Graph descriptionPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Provide a non-empty og:description meta property.

  • https://www.nih.gov/Official website of the National Institutes of Health (NIH). NIH is one of the world's foremost medical research centers. An agency of the U.S. Department of Health and Human Services, the NIH is the Federal focal point for health and medical research. The NIH
Open Graph typePassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Declare og:type, such as website or article.

Open Graph URLPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Set og:url to an absolute HTTP(S) URL for this content.

Open Graph image URLPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Set og:image to an absolute HTTP(S) image URL. Homepage image availability is checked separately.

  • https://www.nih.gov/https://www.nih.gov/sites/default/files/styles/thumbnail_large/public/2025-01/thumbnail-generic.png
Open Graph image descriptionNeeds work

0/1 applicable observations passed. 0.00/1 checklist weight earned.

How to improve: Describe the sharing image with og:image:alt.

Social card typePassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Declare twitter:card as summary or summary_large_image for a website card.

Homepage favicon availablePassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Serve a non-empty public image with an image Content-Type.

Homepage sharing image availablePassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Serve a non-empty public image with an image Content-Type.

Security0 to improve
HTTPS pagePassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Serve the page over HTTPS with a valid certificate.

No insecure embedded resourcesPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Use HTTPS for embedded script, image, stylesheet, frame, audio and video URLs.

HSTS declaredPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Send Strict-Transport-Security on HTTPS responses with max-age of at least 15552000 seconds (180 days); OWASP recommends one year and includeSubDomains. Reference: OWASP HTTP Strict Transport Security cheat sheet, MDN.

Content Security Policy declaredPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Send a Content-Security-Policy header (or a <meta http-equiv="Content-Security-Policy"> on the page) that restricts script and resource sources. This check verifies presence, not policy strength. Reference: OWASP Content Security Policy cheat sheet, MDN.

  • https://www.nih.gov/Content-Security-Policy: default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval' *.nih.gov *.googleapis.com *.govdelivery.com *.hatchbuck.com *.youtube.com *.here.com search.usa.gov *.jquery.com *.crazyegg.com *.addthis.com *.addthisedge.com cdn.js
AI access0 to improve
Content in initial HTMLPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Render meaningful main content on the server so readers can access it without executing JavaScript.

Performance0 to improve
HTML transfer budgetPassed

1/1 applicable observations passed. 1.00/1 checklist weight earned.

How to improve: Keep the uncompressed HTML at or below 500 KB. Remove duplicated inline payloads and unnecessary markup.

Repeated homepage HTTP responsePassed

1/1 applicable observations passed. Informational; excluded from points.

How to improve: Improve server response and CDN caching. Median of three requests; diagnostic only, never a ranking tiebreak.

  • https://www.nih.gov/3/3 successful measurements to response headers. Includes DNS and TLS; excludes rendering.
Browser loading and Core Web VitalsNot verified

0/1 applicable observations passed. Informational; excluded from points.

How to improve: Measure LCP, INP and CLS with browser and field tools.

Checklist quality-v4. Competitive weights: SEO 25%, Accessibility 25%, Structure 25%, Sharing 10%, Security 15%. AI access and Performance are diagnostic only. This expanded report may include pages outside the competitive sample. Unverified scored checks earn no points; not-applicable and manual checks are excluded. Full methodology and references.

HTTP response timings

HTTP response time measured by our crawler; not browser loading speed.

Pages inspected (52)

All 52 pages from this scan.

PageStatusTitleH1ms
https://www.nih.gov/200National Institutes of Health (NIH) |
Page checklist evidence
  • title: passedNational Institutes of Health (NIH) |
  • description: passedOfficial website of the National Institutes of Health (NIH). NIH is one of the world's foremost medical research centers. An agency of the U.S. Department of Health and Human Services, the NIH is the Federal focal point for health and medical research. The NIH
  • canonical: passedhttps://www.nih.gov/
  • h1: failed0 H1 element(s)
  • headings: failed1 skipped heading level(s)
  • main: passed1 main landmarks
  • lang: passeden
  • alt: passed0 of 16 images lack an alt attribute
  • img-dimensions: failed16 of 16 images lack width/height attributes or an aspect-ratio style
  • labels: passed0 of 1 controls have no HTML label
  • buttons: passed0 of 10 buttons have no HTML name
  • links-named: passed0 of 49 links have no HTML name
  • link-text: failed1 of 49 links use generic text: "learn more"
  • viewport: passedwidth=device-width, initial-scale=1.0
  • https: passedhttps://www.nih.gov/
  • mixed: passed0 HTTP embedded resource URL(s)
  • og-title: failedNo og:title
  • og-description: passedOfficial website of the National Institutes of Health (NIH). NIH is one of the world's foremost medical research centers. An agency of the U.S. Department of Health and Human Services, the NIH is the Federal focal point for health and medical research. The NIH
  • og-type: passedArticle
  • og-url: passedhttps://www.nih.gov/node
  • og-image: passedhttps://www.nih.gov/sites/default/files/styles/thumbnail_large/public/2025-01/thumbnail-generic.png
  • og-alt: failedNo sharing image description
  • twitter-card: passedsummary
  • readable: passed1140 characters of crawler-visible content (minimum 100)
  • jsonld: failed0 of 0 blocks have valid JSON-LD structure
  • html-size: passed62,730 bytes of HTML; budget 500,000
0603
https://www.nih.gov/about-nih403—090
https://www.nih.gov/about-nih/contact-us403—074
https://www.nih.gov/about-nih/frequently-asked-questions403—071
https://www.nih.gov/about-nih/get-involved-nih403—084
https://www.nih.gov/about-nih/impact-nih-research403—079
https://www.nih.gov/about-nih/mission-goals403—077
https://www.nih.gov/about-nih/nih-almanac403—083
https://www.nih.gov/about-nih/nih-director403—078
https://www.nih.gov/about-nih/nih-turning-discovery-into-health403—090
https://www.nih.gov/about-nih/organization403—087
https://www.nih.gov/about-nih/science-health-public-trust403—077
https://www.nih.gov/about-nih/visitor-information403—069
https://www.nih.gov/accessibility403—071
https://www.nih.gov/disclaimers403—071
https://www.nih.gov/grants-funding403—083
https://www.nih.gov/health-information403—075
https://www.nih.gov/health-information/nih-clinical-research-trials-you403—083
https://www.nih.gov/health-information/your-healthiest-self-wellness-toolkits403—090
https://www.nih.gov/institutes-nih403—086
https://www.nih.gov/about-nih/what-we-do/impact-nih-research403—077
https://www.nih.gov/about-nih/who-we-are/nih-director403—070
https://www.nih.gov/challenges/nourish-autoimmunity-digital-health-challenge403—080
https://www.nih.gov/heal403—076
https://www.nih.gov/institutes-nih/directors-nih-institutes-centers403—076
https://www.nih.gov/institutes-nih/list-institutes-centers403—070
https://www.nih.gov/institutes-nih/nih-office-director403—076
https://www.nih.gov/institutes-nih/nih-office-director/office-communications-public-liaison/freedom-information-act-office403—079
https://www.nih.gov/institutes-nih/office-communications-public-liaison/clear-communication/talking-your-doctor-or-health-care-provider403—075
https://www.nih.gov/news-events403—071
https://www.nih.gov/news-events/images-b-roll403—075
https://www.nih.gov/news-events/media-inquiries403—084
https://www.nih.gov/news-events/news-releases403—070
https://www.nih.gov/news-events/nih-news-publications403—083
https://www.nih.gov/news-events/nih-social-media403—074
https://www.nih.gov/nih-website-archives403—070
https://www.nih.gov/nondiscrimination-notice403—078
https://www.nih.gov/press-room403—079
https://www.nih.gov/privacy-policy403—070
https://www.nih.gov/research-training403—070
https://www.nih.gov/research-training/accelerating-medicines-partnership-amp403—078
https://www.nih.gov/research-training/clinical-research-resources403—066
https://www.nih.gov/research-training/lasker-clinical-research-scholars403—079
https://www.nih.gov/research-training/library-resources403—081
https://www.nih.gov/research-training/medical-research-initiatives403—075
https://www.nih.gov/research-training/research-nih-labs-clinics403—076
https://www.nih.gov/research-training/research-resources403—072
https://www.nih.gov/research-training/safety-regulation-guidance403—074
https://www.nih.gov/research-training/science-highlights403—0106
https://www.nih.gov/research-training/training-opportunities403—072
https://www.nih.gov/virtual-tour403—075
https://www.nih.gov/web-modernization403—082
Optional AI signals

Informational signals; these do not certify search visibility or unlock S-Tier.

  • llms.txtGuide for AI agents
  • Structured dataJSON-LD on the homepage
  • Semantic HTMLMain and navigation landmarks
Browser measurements · supplementary

Mobile page report

nih.gov

https://nih.gov/

Measured · 9/11/2026, 5:17:58 PM UTC

Redirected to: https://www.nih.gov/

Speed
72
Accessibility
93
SEO basics
45
Main content (LCP)
3.3 s
Layout shifts (CLS)
0.003
Blocking time (TBT)
610 ms
Measurement notes (2)
  • The page may not be loading as expected because your test URL (https://nih.gov/) was redirected to https://www.nih.gov/. Try testing the second URL directly.
  • Lighthouse was unable to reliably load the page you requested. Make sure you are testing the correct URL and that the server is properly responding to all requests. (Status code: 403)

Your next improvements

Measured findings to investigate, ordered by audit score.

1. Page has unsuccessful HTTP status code

Pages with unsuccessful HTTP status codes may not be indexed properly. [Learn more about HTTP status codes](https://developer.chrome.com/docs/lighthouse/seo/http-status-code/).

2. The document uses `<meta http-equiv="refresh">`

Users do not expect a page to refresh automatically, and doing so will move focus back to the top of the page. This may create a frustrating or confusing experience. [Learn more about the refresh meta tag](https://dequeuniversity.com/rules/axe/4.12/meta-refresh).

head > meta · <meta http-equiv="refresh" content="360">
3. Network dependency tree

[Avoid chaining critical requests](https://developer.chrome.com/docs/performance/insights/network-dependency-tree) by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

4. Page is blocked from indexing

Search engines are unable to include your pages in search results if they don't have permission to crawl them. [Learn more about crawler directives](https://developer.chrome.com/docs/lighthouse/seo/is-crawlable/).

5. Document does not have a meta description

Meta descriptions may be included in search results to concisely summarize page content. [Learn more about the meta description](https://developer.chrome.com/docs/lighthouse/seo/meta-description/).

6. LCP breakdown

Each [subpart has specific improvement strategies](https://developer.chrome.com/docs/performance/insights/lcp-breakdown). Ideally, most of the LCP time should be spent on loading the resources, not within delays.

7. Forced reflow

A forced reflow occurs when JavaScript queries geometric properties (such as `offsetWidth`) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about [forced reflows](https://developer.chrome.com/docs/performance/insights/forced-reflow) and possible mitigations.

8. Total Blocking Time

Sum of all time periods between FCP and Time to Interactive, when task length exceeded 50ms, expressed in milliseconds. [Learn more about the Total Blocking Time metric](https://developer.chrome.com/docs/lighthouse/performance/lighthouse-total-blocking-time/).

Fix with your coding assistant

Copy a ready-to-use prompt with the issues and affected URLs.

Battle scoring rules

The arena winner follows the verified ranking: internal link health first, then the published two-decimal quality score. Both sites need two agreeing standard observations. Browser performance, accessibility and SEO are complementary diagnostics and do not move the ranking or decide its winner. Page-only battles compare compatible rounds; performance differences up to five points draw, and equal round wins remain a tie. Missing measurements never count as zero. Browser audits do not certify accessibility. Saved results keep their measured evidence; start a rematch for a newer comparison.