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Accessibility

· 13 checks — Landmarks, headings, alt text, forms, and link quality rolled into one auditable list.
SCORE
47
GRADE
F
FIX
7
REVIEW
4
PASS
2
INFO
0
Checks
13
2 PASS 4 REVIEW 7 FIX
D
Landmark Structure
Action
2 landmarks
FIX
2 landmarks
Critical::
No <main> landmark found
Screen reader users cannot quickly navigate to the primary content. Wrap your main content in <main>.
Warning::
No <nav> landmark found
Warning::
Skip navigation link is missing (WCAG 2.4.1)
Add a skip link as the first focusable element so keyboard users can bypass repeated navigation.
Page Structure — as a screen reader sees it
BANNER header MAIN (missing!) CONTENTINFO footer

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

Add a skip link as the first focusable element so keyboard users can bypass repeated navigation.

Why this matters

Without a skip-nav link, keyboard users tab through every nav item before reaching content — every page, every visit.

Learn more ▾

WCAG 2.4.1 (Bypass Blocks) requires a mechanism to skip past repeated content. The standard implementation is a 'Skip to main content' link that's the first focusable element, visually hidden until focused. Three lines of HTML + four of CSS.

Source: WCAG 2.1 SC 2.4.1

F
Heading Hierarchy
Action
79 headings, 6 skip(s)
FIX
79 headings, 6 skip(s)
Info::
Single H1 present
Warning::
Heading level skipped: H2 → H5 (missing H3)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
Heading level skipped: H2 → H5 (missing H3)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
Heading level skipped: H2 → H5 (missing H3)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
Heading level skipped: H2 → H5 (missing H3)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
Heading level skipped: H2 → H5 (missing H3)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
Heading level skipped: H2 → H5 (missing H3)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
15 empty heading(s)
Empty headings appear in the document outline but provide no information.
  • H1 Welcome to CHM
  • H2 On Now: Apple@50
  • H2 Exhibits
  • H2 Rare Apple Prototypes
  • H2 More Exhibits
  • H5 (empty)
  • H4 Chatbots Decoded: Exploring AI
  • H5 (empty)
  • H4 Revolution: The First 2000 Years of Computing
  • H5 (empty)
  • H4 Make Software: Change the World!
  • H2 Discover More at CHM
  • H5 (empty)
  • H4 Podcast
  • H5 (empty)
  • H4 TechFest
  • H5 Visit
  • H4 Tours
  • H5 Visit
  • H4 Exhibits
  • H5 EXPLORE
  • H4 Collections
  • H5 playlist
  • H4 Source Code
  • H5 Explore
  • H4 Timelines
  • H5 Awards
  • H4 Fellow Awards
  • H5 (empty)
  • H4 Podcast
  • H5 (empty)
  • H4 TechFest
  • H5 Visit
  • H4 Tours
  • H5 Visit
  • H4 Exhibits
  • H5 EXPLORE
  • H4 Collections
  • H5 playlist
  • H4 Source Code
  • H5 Explore
  • H4 Timelines
  • H5 Awards
  • H4 Fellow Awards
  • H5 (empty)
  • H4 Podcast
  • H5 (empty)
  • H4 TechFest
  • H2 CHM Online Store
  • H2 Upcoming Events
  • H5 (empty)
  • H4 2026 Fellow Awards Ceremony
  • H5 (empty)
  • H4 My Year With AI
  • H5 (empty)
  • H4 Steve Jobs in Exile
  • H2 From Our Blogs
  • H5 CHM BLOG skipped
  • H4 A Historic Pixel Art Exhibition
  • H5 CHM BLOG
  • H4 Celebrating Apple at 50
  • H5 CHM BLOG
  • H4 Apple History in Prototypes
  • H2 Activities & Resources
  • H5 Game for Grades 3–8 skipped
  • H4 Roblox
  • H5 Activity for Grades 6–16
  • H4 Minecraft: Education Edition
  • H5 Activity for Grades 6–12
  • H4 Revolution Virtual Scavenger Hunt
  • H2 CHM on YouTube
  • H5 (empty)
  • H4 CHM Live
  • H5 (empty)
  • H4 CHM Bytes
  • H5 (empty)
  • H4 CHM YouTube Shorts
  • H2 HELP US TELL THE FULL STORY
  • H2 Hours and Directions

Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.

Why this matters

Skipping heading levels breaks the document outline — screen-reader users lose track of section nesting.

Learn more ▾

Screen reader users navigate by jumping between headings (H1 → H2 → H3). Skipping (H1 → H3) breaks the sense of hierarchy. Use sequential levels even if you don't like the default styling — restyle with CSS instead. WCAG 1.3.1 (Info and Relationships) treats this as an A failure.

Source: WCAG 2.1 SC 1.3.1 / W3C WAI

Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.

Why this matters

Skipping heading levels breaks the document outline — screen-reader users lose track of section nesting.

Learn more ▾

Screen reader users navigate by jumping between headings (H1 → H2 → H3). Skipping (H1 → H3) breaks the sense of hierarchy. Use sequential levels even if you don't like the default styling — restyle with CSS instead. WCAG 1.3.1 (Info and Relationships) treats this as an A failure.

Source: WCAG 2.1 SC 1.3.1 / W3C WAI

Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.

Why this matters

Skipping heading levels breaks the document outline — screen-reader users lose track of section nesting.

Learn more ▾

Screen reader users navigate by jumping between headings (H1 → H2 → H3). Skipping (H1 → H3) breaks the sense of hierarchy. Use sequential levels even if you don't like the default styling — restyle with CSS instead. WCAG 1.3.1 (Info and Relationships) treats this as an A failure.

Source: WCAG 2.1 SC 1.3.1 / W3C WAI

Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.

Why this matters

Skipping heading levels breaks the document outline — screen-reader users lose track of section nesting.

Learn more ▾

Screen reader users navigate by jumping between headings (H1 → H2 → H3). Skipping (H1 → H3) breaks the sense of hierarchy. Use sequential levels even if you don't like the default styling — restyle with CSS instead. WCAG 1.3.1 (Info and Relationships) treats this as an A failure.

Source: WCAG 2.1 SC 1.3.1 / W3C WAI

Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.

Why this matters

Skipping heading levels breaks the document outline — screen-reader users lose track of section nesting.

Learn more ▾

Screen reader users navigate by jumping between headings (H1 → H2 → H3). Skipping (H1 → H3) breaks the sense of hierarchy. Use sequential levels even if you don't like the default styling — restyle with CSS instead. WCAG 1.3.1 (Info and Relationships) treats this as an A failure.

Source: WCAG 2.1 SC 1.3.1 / W3C WAI

Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.

Why this matters

Skipping heading levels breaks the document outline — screen-reader users lose track of section nesting.

Learn more ▾

Screen reader users navigate by jumping between headings (H1 → H2 → H3). Skipping (H1 → H3) breaks the sense of hierarchy. Use sequential levels even if you don't like the default styling — restyle with CSS instead. WCAG 1.3.1 (Info and Relationships) treats this as an A failure.

Source: WCAG 2.1 SC 1.3.1 / W3C WAI

Empty headings appear in the document outline but provide no information.

Why this matters

Empty <hN> tags break the document outline — screen-reader users navigating by heading hit dead silence.

Source: WCAG 2.4.6

D
Favicon & Branding
Action
3 icon(s) detected
FIX
3 icon(s) detected
Info::
favicon.ico present at site root
Info::
HTML icon links detected
Info::
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 Present
✓ PNG Icons Present
✗ Apple Touch Missing
✗ SVG Favicon Missing
✗ Manifest Icons Missing
✗ Multiple Sizes Missing
D
Web Manifest
Action
Not found
FIX
Not found
Info::
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.

D
Dark Mode Support
Action
No dark mode signals
FIX
No dark mode signals
Info::
No dark mode signals detected
Consider adding CSS with @media (prefers-color-scheme: dark) and <meta name='color-scheme' content='light dark'>.
Info::
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.

D
Print Stylesheet
Action
No print styles
FIX
No print styles
Info::
No print-specific styles detected
When users print this page, they get the screen layout including navigation and non-essential elements. Add @media print rules to hide navigation and optimize layout for paper.
Print Stylesheet No Print Styles
Print stylesheet Not found ✗Inline @media print Not detected ✗
F
Navigation UX
Action
No navigation patterns
FIX
No navigation patterns
Info::
No breadcrumbs, search, or skip link detected
These navigation aids help users orient themselves and find content efficiently, especially on large sites.
Breadcrumbs
Search
Skip Link
Labeled Navigation
Back to Top
Hamburger Menu
Sticky Navigation Cannot reliably detect (CSS-based)
0 of 6 testable patterns navigation patterns detected. Limited navigation support. Consider adding breadcrumbs, search, and skip link.
B
Alt Text Quality
2 of 25 images have issues
REVIEW
2 of 25 images have issues
Critical::
2 image(s) missing alt attribute
Images without alt text are invisible to screen readers.
Info::
23 image(s) with good alt text
25 images 23 good alt text 2 missing
IssueCount
missing2 image(s)

Images without alt text are invisible to screen readers.

Why this matters

Each image without alt text is a WCAG 1.1.1 failure — invisible to screen-reader users, lost from Google Image Search.

Learn more ▾

WCAG 2.1 Level A requires text alternatives for non-decorative images. Empty alt='' is fine for decorative; meaningful images need descriptive text. Common fixes: CMS audit + bulk add, build-time linter (alt-text-required ESLint rule), CI gate on Lighthouse a11y score.

Source: WCAG 2.1 SC 1.1.1 / WebAIM Million Report

C
Form Accessibility
Action
3 of 4 controls have issues
REVIEW
3 of 4 controls have issues
Critical::
3 control(s) without accessible label
Form controls need a <label>, aria-label, or aria-labelledby for screen readers.
Got: <input type="submit" id="searchsubmit">; <textarea name="g-recaptcha-response" id="g-recaptcha-response-100000">; <textarea name="g-recaptcha-response" id="g-recaptcha-response-100001">
Info::
1 control(s) properly labeled
4 controls
1 labeled
0 placeholder only
3 unlabeled
ControlTypeLabelMethod
#stextSearch for:for/id
#searchsubmitsubmit(none)none
#g-recaptcha-response-100000textarea(none)none
#g-recaptcha-response-100001textarea(none)none

Form controls need a <label>, aria-label, or aria-labelledby for screen readers.

<input type="submit" id="searchsubmit">; <textarea name="g-recaptcha-response" id="g-recaptcha-response-100000">; <textarea name="g-recaptcha-response" id="g-recaptcha-response-100001">

Why this matters

Form controls without labels — assistive tech announces 'edit text' with no context; users can't complete forms.

Source: WCAG 2.1 SC 3.3.2

C
Color Contrast (Screenshot)
Action
20 text elements analyzed, 2 fail WCAG AA
REVIEW

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

18 pass 2 fail WCAG AA
a Tickets
1.66:1
#000000
on
#2E3437
needs 4.5:1 (normal text)
16px · top of page (header area)
span Menu
4.27:1
#000000
on
#687278
needs 4.5:1 (normal text)
16px · top of page (header area) · 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)
ElementRatioRequiredFGBGResult
h1 Welcome to CHM21.00:13.0:1
#000000
#FFFFFF
Pass
h2 On Now: Apple@5021.00:13.0:1
#000000
#FFFFFF
Pass
h2 Exhibits21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Rare Apple Prototype…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 More Exhibits21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Discover More at CHM21.00:13.0:1
#000000
#FFFFFF
Pass
h2 CHM Online Store21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Upcoming Events21.00:13.0:1
#000000
#FFFFFF
Pass
h2 From Our Blogs21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Activities & Resourc…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 CHM on YouTube21.00:13.0:1
#000000
#FFFFFF
Pass
h2 HELP US TELL THE FUL…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Hours and Directions21.00:13.0:1
#000000
#FFFFFF
Pass
title Home - CHM21.00:14.5:1
#000000
#FFFFFF
Pass
a Donate21.00:14.5:1
#000000
#FFFFFF
Pass
a Tickets1.66:14.5:1
#000000
#2E3437
Fail
span Menu4.27:14.5:1
#000000
#687278
Fail
a Explore12.27:14.5:1
#000000
#B5C9D4
Pass
a Overview11.21:14.5:1
#000000
#AEC0CC
Pass
a Collections9.38:14.5:1
#000000
#98B1BF
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
404 Error Page
HTTP 404, custom page
PASS
HTTP 404, custom page
Info::
Correct 404 status code returned
Got: HTTP 404
Info::
Custom styled 404 page
Info::
Navigation links present on 404 page
Info::
Homepage link present on 404 page
Info::
Search form present on 404 page
404 Page Quality ✓ Custom 404 Page
Status Code HTTP 404 ✓Page Title Page not found - CHM ✓Custom Styling ✓Navigation ✓Homepage Link ✓Search Form ✓
A+
Lighthouse Accessibility Audits
Score 96/100 — 2 failing, 22 passed
PASS
96

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.

Navigation

Properly ordered headings that do not skip levels convey the semantic structure of the page, making it easier to navigate and understand when using assistive technologies. Learn more about heading order.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.related-articles__column > a > div.related-articles__content > h5 div.related-articles__column > a > div.related-articles__content > h5
Visit div.slider__container > div.slider__content > a > h5
div.related-articles__column > a > div.related-articles__content > h5 div.related-articles__column > a > div.related-articles__content > h5
CHM BLOG div.related-articles__column > a > div.related-articles__content > h5
Game for Grades 3–8 div.related-articles__column > a > div.related-articles__content > h5
div.related-articles__column > a > div.related-articles__content > h5 div.related-articles__column > a > div.related-articles__content > h5

These are opportunities to improve keyboard navigation in your application.

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.no-js html.no-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>`
●`[aria-*]` attributes have valid values
●`[aria-*]` attributes are valid and not misspelled
●Buttons have an accessible name
●Image elements have `[alt]` attributes
●`[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
●Background and foreground colors have a sufficient contrast ratio
●Document has a `<title>` element
●`<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.
●All heading elements contain content.
●Identical links have the same purpose.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○Deprecated ARIA roles were not used
○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
○`[role]`s have all required `[aria-*]` attributes
○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
○`[role]` values are valid
○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
○`<frame>` or `<iframe>` elements have a title
○`<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
○Form elements have associated labels
○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>`.
○Uses ARIA roles only on compatible elements
○Image elements do not have `[alt]` attributes that are redundant text.
○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.

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