Accessibility

· 13 checks — Landmarks, headings, alt text, forms, and link quality rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

Checks

5 PASS 4 REVIEW 4 FIX

Favicon & Branding

Action

1 icon(s) detected

FIX

1 icon(s) detected

No favicon.ico at site root

Some older browsers, bookmark tools, and RSS readers look for /favicon.ico. Add one as a fallback.

HTML icon links detected

No apple-touch-icon detected

iOS devices use this when users add your site to their home screen. Add <link rel='apple-touch-icon' sizes='180x180' href='/apple-touch-icon.png'>.

✗ favicon.ico Missing

✓ PNG Icons Present

✗ Apple Touch Missing

✗ SVG Favicon Missing

✗ Manifest Icons Missing

✗ Multiple Sizes Missing

Web Manifest

Action

Not found

FIX

Not found

No web manifest found

No manifest at standard paths (/manifest.json, /site.webmanifest). A manifest is optional but enables PWA features like home screen installation and standalone display.

No web manifest found.

Dark Mode Support

Action

No dark mode signals

FIX

No dark mode signals

No dark mode signals detected

Consider adding CSS with @media (prefers-color-scheme: dark) and <meta name='color-scheme' content='light dark'>.

Detection limited to meta tags and inline styles

External CSS files may contain prefers-color-scheme rules not visible to this scan.

Dark ModeNo Dark Mode Detected

color-scheme meta Not set ✗Dark theme-color Not set ✗CSS indicators Not detected ✗

Detection limited to meta tags and inline styles.

Landmark Structure

Action

7 landmarks

REVIEW

7 landmarks

No <main> landmark found

Screen reader users cannot quickly navigate to the primary content. Wrap your main content in <main>.

3 <nav> landmark(s) found

1 of 3 <nav> elements are unlabeled

Multiple navigations need aria-label to distinguish them for screen readers.

Skip navigation link present

Page Structure — as a screen reader sees it

Screen reader users cannot quickly navigate to the primary content. Wrap your main content in <main>.

Why this matters

Without a <main> landmark, screen-reader users can't skip past the navigation to the page content — every page starts with re-reading the menu.

Learn more ▾

The <main> element marks the page's primary content area. Assistive tech offers a 'jump to main' shortcut — but only if <main> exists. Without it, every page navigation forces re-reading the header. Wrap your primary content in a single <main>.

Source: WAI-ARIA / WCAG 2.4.1

Multiple navigations need aria-label to distinguish them for screen readers.

Why this matters

Some <nav> elements lack aria-label — screen-reader users hear 'navigation' multiple times with no way to distinguish them.

Learn more ▾

When a page has multiple <nav> regions (primary, footer, breadcrumb), each needs aria-label or aria-labelledby. AT users navigate by landmark; identical 'navigation' announcements force them to enter each one to discover purpose.

Source: WAI-ARIA Authoring Practices

Heading Hierarchy

15 headings

REVIEW

15 headings

No H1 heading found

Every page should have one H1 that describes the page content.

H2 125 Years of Driving Innovation
H2 What we do
H2 CHIPS for America
H2 What’s new
H3 NIST Weighs In on the Mystery of the Gravitational Constant
H3 How a NISTer Watches ‘Project Hail Mary’
H3 Any Color You Like: NIST Scientists Create ‘Any Wavelength’ Lasers in Tiny Circuits for Light
H3 Mundane Measurements Have Made Astronomy Possible for More Than 100 Years
H3 5 Weirdly Nonstandard Things About the Metric System
H3 Buried, Forgotten and Found: The Story of NIST’s 1916 Time Capsule
H3 NIST Helps Fingerprint Examiners With New Data and Software Release
H3 How a Forensic Anthropologist Thinks About Human Remains Research — and What It Means for Our Humanity
H2 America’s national measurement institute
H2 NIST in your inbox
H3 HEADQUARTERS

Every page should have one H1 that describes the page content.

Why this matters

No H1 means screen-reader users can't identify the page's primary topic, and Google's content-extraction degrades.

Learn more ▾

The H1 is the document title for assistive tech and a strong signal to search engines about page topic. Pages without one force screen readers to fall back to the <title> attribute or page chrome. Add a single H1 that names the page's primary subject.

Source: WCAG 2.4.6 / Google Search Central

Link & Button Quality

3 issue(s) across 157 links and 10 buttons

REVIEW

3 issue(s) across 157 links and 10 buttons

1 link(s) with no accessible text

Links without text are announced as raw URLs by screen readers.

Got: a#main-content

1 link(s) with generic text

Generic link text like 'click here' doesn't describe the destination.

Got: /chips ("Learn more")

1 button(s) with no accessible text

Icon-only buttons need an aria-label so screen readers can announce them.

Got: button.usa-button (#119 on page)

155 link(s) with descriptive text

157 links

1 empty

1 generic text

0 new tab

1 empty buttons

Element	Text	Issue	Suggested Fix
	(empty)	empty	Add link text or aria-label
/chips	Learn more	generic text	Replace with descriptive text
Before: Learn more Suggested: Chips
<button>	(empty)	empty	Add button text or aria-label

164 links and buttons have descriptive text

Links without text are announced as raw URLs by screen readers.

a#main-content

Why this matters

Links with no accessible text (empty <a></a>, image-only no alt, icon-only no aria-label) are unidentifiable to screen readers.

Source: WCAG 2.1 SC 2.4.4

Generic link text like 'click here' doesn't describe the destination.

/chips ("Learn more")

Why this matters

Generic anchor text ('click here', 'read more', 'learn more') tells screen readers and search engines nothing about the destination.

Learn more ▾

Out-of-context lists of links read by AT (one navigation pattern) become useless when every link says 'click here'. Use the destination's title or topic as anchor text. Doubles as SEO win — Google passes anchor-text relevance to the destination.

Source: WCAG 2.4.4 / Google Search Central

Icon-only buttons need an aria-label so screen readers can announce them.

button.usa-button (#119 on page)

Why this matters

Buttons with no accessible text (icon-only, no aria-label) can't be activated by voice control or understood by screen readers.

Source: WCAG 2.1 SC 4.1.2

Color Contrast (Screenshot)

Action

20 text elements analyzed, 5 fail WCAG AA

REVIEW

Analyzes text contrast against the actual rendered page, including background images, gradients, and overlays that CSS-based tools cannot detect.

15 pass 5 fail WCAG AA 3 pass AA only

p An official website of the United States…

1.00:1

#000000

needs 4.5:1 (normal text)

16px · top of page (header area)

p Here’s how you know

1.00:1

#000000

needs 4.5:1 (normal text)

16px · top of page (header area)

span Here’s how you know

1.00:1

#000000

needs 4.5:1 (normal text)

16px · above the fold

strong Official websites use .gov

1.00:1

#000000

needs 3.0:1 (large text)

16px · above the fold

p website belongs to an official governmen…

3.39:1

#000000

#6B5F55

needs 4.5:1 (normal text)

16px · above the fold · over background image/gradient

1 contrast failures on background images/gradients

These failures are invisible to CSS-based accessibility tools like Lighthouse. The text may be fine on a solid background, but fails when rendered over an image or gradient.

Show all checked elements (20)

Element	Ratio	Required	FG	BG	Result
h2 125 Years of Driving…	21.00:1	3.0:1	#000000	#FFFFFF	Pass
h2 What we do	21.00:1	3.0:1	#000000	#FFFFFF	Pass
h2 What’s new	21.00:1	3.0:1	#000000	#FFFFFF	Pass
h2 America’s national…	21.00:1	3.0:1	#000000	#FFFFFF	Pass
h2 NIST in your inbox	21.00:1	3.0:1	#000000	#FFFFFF	Pass
h3 NIST Weighs In on th…	21.00:1	3.0:1	#000000	#FFFFFF	Pass
h3 How a NISTer Watches…	21.00:1	3.0:1	#000000	#FFFFFF	Pass
h3 Any Color You Like: …	21.00:1	3.0:1	#000000	#FFFFFF	Pass
h3 Mundane Measurements…	21.00:1	3.0:1	#000000	#FFFFFF	Pass
h3 HEADQUARTERS	21.00:1	3.0:1	#000000	#FFFFFF	Pass
title National Institute o…	18.43:1	4.5:1	#000000	#F0F0F0	Pass
a Skip to main content	6.58:1	4.5:1	#000000	#909090	Pass
p An official website …	1.00:1	4.5:1	#000000	#000000	Fail
p Here’s how you kno…	1.00:1	4.5:1	#000000	#000000	Fail
span Here’s how you kno…	1.00:1	4.5:1	#000000	#000000	Fail
strong Official websites us…	1.00:1	3.0:1	#000000	#000000	Fail
strong .gov	9.29:1	3.0:1	#000000	#B0ACA5	Pass
p website belongs to a…	3.39:1	4.5:1	#000000	#6B5F55	Fail
strong Secure .gov websites…	3.37:1	3.0:1	#000000	#695F56	Pass
strong lock	3.62:1	3.0:1	#000000	#6D645B	Pass

Methodology: The top 20 text elements by font size were checked. Background color was sampled from the desktop screenshot using a 5-point pattern. WCAG 2.1 AA requires 4.5:1 for normal text and 3:1 for large text.

A+

Alt Text Quality

All 20 images OK

PASS

All 20 images OK

2 image(s) with alt text over 125 characters

2 decorative image(s) correctly marked

16 image(s) with good alt text

20 images 16 good alt text 2 decorative

Issue	Count
too long	2 image(s)

A+

Form Accessibility

All 1 controls labeled

PASS

All 1 controls labeled

1 control(s) properly labeled

1 controls

1 labeled

0 placeholder only

0 unlabeled

Control	Type	Label	Method
#search-form	search	Search NIST	for/id

404 Error Page

HTTP 404, custom page

PASS

HTTP 404, custom page

Correct 404 status code returned

Got: HTTP 404

Custom styled 404 page

Navigation links present on 404 page

Homepage link present on 404 page

Search form present on 404 page

404 Page Quality ✓ Custom 404 Page

Status Code HTTP 404 ✓Page Title Lock ✓Custom Styling ✓Navigation ✓Homepage Link ✓Search Form ✓

A+

Print Stylesheet

Print styles detected

PASS

Print styles detected

External print stylesheet detected

Got: /sites/default/files/css/css_LpHBc8EPEsDrEJSd96BC5X0OHJG9W5P68QT2eD_fJio.css?delta=2&language=en&theme=nist_www&include=eJxlj9EOwiAMRX-IyCc1BSrgCiXAwvx7mVOzxbd7TprbFtcugNkGqU3jCZRBu8DkLkWfMkQrWVmppF1dC_INH7hdhIvI4hVtnWNevvaDKsfWtWcxyO8MBT3BncjtW_S_OqZ6oETzAGGDFZI47WJDwwS_VhhjXJp3DpJor1Pt2Tql-UqjFx-_YAo

Print Stylesheet ✓ Print Optimized

Print stylesheet /sites/default/files/css/css_LpHBc8EPEsDrEJSd96BC5X0OHJG9W5P68QT2eD_fJio.css?delta=2&language=en&theme=nist_www&include=eJxlj9EOwiAMRX-IyCc1BSrgCiXAwvx7mVOzxbd7TprbFtcugNkGqU3jCZRBu8DkLkWfMkQrWVmppF1dC_INH7hdhIvI4hVtnWNevvaDKsfWtWcxyO8MBT3BncjtW_S_OqZ6oETzAGGDFZI47WJDwwS_VhhjXJp3DpJor1Pt2Tql-UqjFx-_YAo ✓Inline @media print Not detected ✗

A+

Lighthouse Accessibility Audits

Score 95/100 — 2 failing, 25 passed

PASS

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

Contrast

Low-contrast text is difficult or impossible for many users to read. Learn how to provide sufficient color contrast.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
See NIST News `div.bg-base-lightest > div.grid-container > div.nist-page-segment > a.usa-button`

These are opportunities to improve the legibility of your content.

Best practices

One main landmark helps screen reader users navigate a web page. Learn more about landmarks.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html.js `html.js`

These items highlight common accessibility best practices.

○Interactive controls are keyboard focusable

○Interactive elements indicate their purpose and state

○The page has a logical tab order

○Visual order on the page follows DOM order

○User focus is not accidentally trapped in a region

○The user's focus is directed to new content added to the page

○HTML5 landmark elements are used to improve navigation

○Offscreen content is hidden from assistive technology

○Custom controls have associated labels

○Custom controls have ARIA roles

●`[aria-*]` attributes match their roles

●`[aria-hidden="true"]` is not present on the document `<body>`

●`[role]`s have all required `[aria-*]` attributes

●`[role]` values are valid

●`[aria-*]` attributes have valid values

●`[aria-*]` attributes are valid and not misspelled

●Buttons have an accessible name

●Image elements have `[alt]` attributes

●Form elements have associated labels

●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.

●ARIA attributes are used as specified for the element's role

●`[aria-hidden="true"]` elements do not contain focusable descendents

●Elements use only permitted ARIA attributes

●Document has a `<title>` element

●`<frame>` or `<iframe>` elements have a title

●`<html>` element has a `[lang]` attribute

●`<html>` element has a valid value for its `[lang]` attribute

●Links are distinguishable without relying on color.

●Links have a discernible name

●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements

●No element has a `[tabindex]` value greater than 0

●Touch targets have sufficient size and spacing.

●Heading elements appear in a sequentially-descending order

●Deprecated ARIA roles were not used

○`[accesskey]` values are unique

○`button`, `link`, and `menuitem` elements have accessible names

○Elements with `role="dialog"` or `role="alertdialog"` have accessible names.

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.

○`[role]`s are contained by their required parent element

○Elements with the `role=text` attribute do not have focusable descendents.

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○ARIA `treeitem` elements have accessible names

○The page contains a heading, skip link, or landmark region

○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.

○Definition list items are wrapped in `<dl>` elements

○ARIA IDs are unique

○No form fields have multiple labels

○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.

○Input buttons have discernible text.

○`<input type="image">` elements have `[alt]` text

○The document does not use `<meta http-equiv="refresh">`

○`<object>` elements have alternate text

○Select elements have associated label elements.

○Skip links are focusable.

○Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.

○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.

○`[lang]` attributes have a valid value

○`<video>` elements contain a `<track>` element with `[kind="captions"]`

○Tables have different content in the summary attribute and `<caption>`.

○All heading elements contain content.

○Uses ARIA roles only on compatible elements

○Image elements do not have `[alt]` attributes that are redundant text.

○Identical links have the same purpose.

○Elements with visible text labels have matching accessible names.

○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.

○`<td>` elements in a large `<table>` have one or more table headers.

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.