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Accessibility

· 13 checks — Landmarks, headings, alt text, forms, and link quality rolled into one auditable list.
SCORE
58
GRADE
D
FIX
5
REVIEW
3
PASS
5
INFO
0
Checks
13
5 PASS 3 REVIEW 5 FIX
F
Heading Hierarchy
Action
62 headings, 7 skip(s)
FIX
62 headings, 7 skip(s)
Warning::
Multiple H1 headings (2 found)
A page should have only one H1. Multiple H1s dilute the document outline.
Warning::
Heading level skipped: H1 → H3 (missing H2)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
Heading level skipped: H2 → H4 (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 → H4 (missing H3)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
Heading level skipped: H2 → H6 (missing H3)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
Heading level skipped: H1 → H4 (missing H2)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
Heading level skipped: H4 → H6 (missing H5)
Skipping heading levels breaks the document outline. Screen readers may interpret missing levels as structural errors.
Warning::
1 empty heading(s)
Empty headings appear in the document outline but provide no information.
  • H4 Main navigation
  • H1 10 times the power at a fraction of the cost!
  • H3 0+ skipped
  • H3 0M+
  • H3 0+
  • H3 0K+
  • H3 0K+
  • H2 LibreTexts is your go-to source for Training, Content, Development, and Technology for a ideal blend of Open Education Resources
  • H4 Content skipped
  • H4 Technology
  • H4 Development
  • H4 Training
  • H2 (empty)
  • H3 Upcoming Events
  • H2 What can LibreTexts Help with?
  • H5 Textbook Libraries skipped
  • H5 Homework/Assessment
  • H5 Interactive Learning Materials
  • H2 Check out our Latest Blogs
  • H4 LibreTexts March 2026 Newsletter skipped
  • H4 LibreTexts February 2026 Newsletter
  • H4 OpenEd Week 2026 is Right Around the Corner
  • H4 Pagination
  • H2 What Instructors say about us...
  • H6 Brian Lindshield skipped
  • H6 Shelli Wynants
  • H6 Ryan Edwards
  • H6 Heather Evans
  • H6 Shagun Kaur
  • H6 Kim Ernstmeyer
  • H6 Shagun Kaur
  • H6 Dr. Deborah Gustlin
  • H6 Cristina Moon, Ph.D.
  • H6 Rachel Fleming
  • H6 Armeda Reitzel
  • H6 Paul Seeburger
  • H6 Dr. Larry Green
  • H6 Ying Liu
  • H6 Cristina Moon
  • H6 Brian Lindshield
  • H6 Shelli Wynants
  • H6 Ryan Edwards
  • H6 Heather Evans
  • H6 Shagun Kaur
  • H6 Kim Ernstmeyer
  • H6 Shagun Kaur
  • H6 Dr. Deborah Gustlin
  • H6 Cristina Moon, Ph.D.
  • H6 Rachel Fleming
  • H6 Armeda Reitzel
  • H6 Paul Seeburger
  • H6 Dr. Larry Green
  • H6 Ying Liu
  • H6 Cristina Moon
  • H6 Brian Lindshield
  • H1 Join a Global Community! duplicate H1
  • H4 Quick Links skipped
  • H4 Contact Us
  • H6 Faculty Information: skipped
  • H4 Footer Bottom
  • H2 Support Center
  • H3 How can we help you today?

A page should have only one H1. Multiple H1s dilute the document outline.

Why this matters

Multiple H1s blur the page's primary topic — screen-reader users and Google both prefer one H1.

Learn more ▾

HTML5's outline algorithm technically allows multiple H1s within sectioning content, but no browser implements it. In practice: one H1 per page. Use H2-H6 for subsections.

Source: WCAG 2.4.6 / Google Search Central

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

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

F
Favicon & Branding
Action
1 icon(s) detected
FIX
1 icon(s) detected
Warning::
No favicon.ico at site root
Some older browsers, bookmark tools, and RSS readers look for /favicon.ico. Add one as a fallback.
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 Missing
✓ 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.

C
404 Error Page
Action
HTTP 404, custom page
REVIEW
HTTP 404, custom page
Info::
Correct 404 status code returned
Got: HTTP 404
Info::
Custom styled 404 page
Info::
Homepage link present on 404 page
404 Page Quality ✓ Custom 404 Page
Status Code HTTP 404 ✓Page Title 404 | LibreTexts ✓Custom Styling ✓Navigation ✗Homepage Link ✓Search Form ✗
C
Navigation UX
Action
2 navigation pattern(s)
REVIEW
2 navigation pattern(s)
Info::
Search functionality detected
Got: role-search
Info::
Skip navigation link detected
Info::
6 navigation landmark(s) detected
Info::
Hamburger menu detected (responsive design)
Breadcrumbs
Search role='search' landmark
Skip Link Skip link detected
Labeled Navigation 6 <nav> element(s)
Back to Top
Hamburger Menu
Sticky Navigation Cannot reliably detect (CSS-based)
4 of 6 testable patterns navigation patterns detected. Strong navigation UX with multiple discovery paths.
C
Color Contrast (Screenshot)
Action
20 text elements analyzed, 8 fail WCAG AA
REVIEW

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

12 pass 8 fail WCAG AA
a Home
2.03:1
#000000
on
#404040
needs 4.5:1 (normal text)
16px · top of page (header area)
a Academy
1.39:1
#000000
on
#262626
needs 4.5:1 (normal text)
16px · above the fold · over background image/gradient
a Resources
1.53:1
#000000
on
#2D2D2E
needs 4.5:1 (normal text)
16px · above the fold
a Libraries
1.22:1
#000000
on
#1A1B1C
needs 4.5:1 (normal text)
16px · above the fold · over background image/gradient
a Biology
1.00:1
#000000
on
#000000
needs 4.5:1 (normal text)
16px · above the fold
a Business
2.03:1
#000000
on
#404040
needs 4.5:1 (normal text)
16px · above the fold
a Chemistry
2.03:1
#000000
on
#404040
needs 4.5:1 (normal text)
16px · above the fold
a Engineering
1.47:1
#000000
on
#3E2507
needs 4.5:1 (normal text)
16px · above the fold

2 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 10 times the power a…21.00:13.0:1
#000000
#FFFFFF
Pass
h1 Join a Global Commun…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 LibreTexts is your g…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 What can LibreTexts …21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Check out our Latest…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 What Instructors say…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Support Center21.00:13.0:1
#000000
#FFFFFF
Pass
h3 Upcoming Events21.00:13.0:1
#000000
#FFFFFF
Pass
h3 How can we help you …21.00:13.0:1
#000000
#FFFFFF
Pass
title Home | LibreTexts21.00:14.5:1
#000000
#FFFFFF
Pass
a Skip to main content21.00:14.5:1
#000000
#FFFFFF
Pass
h4 Main navigation6.25:13.0:1
#000000
#8C8C8C
Pass
a Home2.03:14.5:1
#000000
#404040
Fail
a Academy1.39:14.5:1
#000000
#262626
Fail
a Resources1.53:14.5:1
#000000
#2D2D2E
Fail
a Libraries1.22:14.5:1
#000000
#1A1B1C
Fail
a Biology1.00:14.5:1
#000000
#000000
Fail
a Business2.03:14.5:1
#000000
#404040
Fail
a Chemistry2.03:14.5:1
#000000
#404040
Fail
a Engineering1.47:14.5:1
#000000
#3E2507
Fail

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
Landmark Structure
11 landmarks
PASS
11 landmarks
Info::
<main> landmark present
Info::
6 <nav> landmark(s) found
Warning::
1 of 6 <nav> elements are unlabeled
Multiple navigations need aria-label to distinguish them for screen readers.
Info::
Skip navigation link present
Info::
Search landmark present
Page Structure — as a screen reader sees it
BANNER header NAV SEARCH MAIN CONTENTINFO footer

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

A
Alt Text Quality
All 39 images OK
PASS
All 39 images OK
Info::
3 image(s) with alt text over 125 characters
Info::
17 decorative image(s) correctly marked
Info::
19 image(s) with good alt text
39 images 19 good alt text 17 decorative
IssueCount
too long3 image(s)
A
Form Accessibility
1 of 1 controls have issues
PASS
1 of 1 controls have issues
Warning::
1 control(s) rely on placeholder only
Placeholder text disappears on focus and is not a reliable label.
Got: <input type="text" name="keys">
1 controls
0 labeled
1 placeholder only
0 unlabeled
ControlTypeLabelMethod
keystext(Search Here...)placeholder only

Placeholder text disappears on focus and is not a reliable label.

<input type="text" name="keys">

Why this matters

Placeholder-only labels disappear when the user starts typing — they must remember what the field was for.

Learn more ▾

Placeholders are NOT labels. They vanish on input, fail color contrast checks (most are gray), and don't satisfy WCAG SC 3.3.2. Always use a real <label> alongside (or aria-labelledby).

Source: WCAG 2.1 SC 3.3.2 / Nielsen Norman

A+
Print Stylesheet
Print styles detected
PASS
Print styles detected
Info::
External print stylesheet detected
Got: /themes/contrib/bootstrap_barrio/css/print.css?sz83xb
Print Stylesheet ✓ Print Optimized
Print stylesheet /themes/contrib/bootstrap_barrio/css/print.css?sz83xb ✓Inline @media print Not detected ✗
A
Lighthouse Accessibility Audits
Score 93/100 — 2 failing, 28 passed
PASS
93

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.

Names and labels

When a button doesn't have an accessible name, screen readers announce it as "button", making it unusable for users who rely on screen readers. Learn how to make buttons more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot
div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot div.carousel1 > div.owl-carousel > div.owl-dots > button.owl-dot

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

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
500+ div.row > div.col-12 > div.counter-content > h3
Content div.body-content > div.elementor-element > div.elementor-widget-container > h4
Textbook Libraries div.content > div.main-content > a.icon > h5
LibreTexts March 2026 Newsletter div.col-lg-4 > div.content-wrapper > div.content-wrapper > h4
Brian Lindshield div.content-block > div.info-content > div.details > h6
Quick Links div.row > div.col-12 > nav#block-quicklinks > h4#block-quicklinks-menu
Faculty Information: div.col-12 > nav#block-contactus > div.footer-info > h6

These are opportunities to improve keyboard navigation in your application.

○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
●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.
●`button`, `link`, and `menuitem` elements have accessible names
●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.
●Document has a main landmark.
●Deprecated ARIA roles were not used
●All heading elements contain content.
●Uses ARIA roles only on compatible elements
●Identical links have the same purpose.
●Elements with visible text labels have matching accessible names.
○`[accesskey]` values are unique
○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
○`<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>`.
○Image elements do not have `[alt]` attributes that are redundant text.
○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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