Skip to content
https://oreilly.com

Accessibility

· 13 checks — Landmarks, headings, alt text, forms, and link quality rolled into one auditable list.
SCORE
53
GRADE
F
FIX
7
REVIEW
1
PASS
5
INFO
0
Checks
13
5 PASS 1 REVIEW 7 FIX
F
404 Error Page
Action
HTTP 403, bare page
FIX
HTTP 403, bare page
Warning::
Unexpected status code: HTTP 403
Expected HTTP 404 but received 403. This may confuse search engine crawlers.
Got: HTTP 403
Warning::
Bare server default 404 page
The 404 page has no custom styling. Users hitting a broken link see a generic error with no way to navigate back. Add a custom 404 page with your site navigation and a search bar.
404 Page Quality Default 404 Page
Status Code HTTP 403 ✗Page Title Access Denied ✓Custom Styling ✗Navigation ✗Homepage Link ✗Search Form ✗
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.

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
1 navigation pattern(s)
FIX
1 navigation pattern(s)
Info::
Skip navigation link detected
Info::
4 navigation landmark(s) detected
Info::
Hamburger menu detected (responsive design)
Breadcrumbs
Search
Skip Link Skip link detected
Labeled Navigation 4 <nav> element(s)
Back to Top
Hamburger Menu
Sticky Navigation Cannot reliably detect (CSS-based)
3 of 6 testable patterns navigation patterns detected. Strong navigation UX with multiple discovery paths.
B
Lighthouse Accessibility Audits
Score 87/100 — 3 failing, 27 passed
REVIEW
87

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
Testimonial video thumbnail 1 div.content > div.home-testimonial-figure > div.home-testimonial-thumbnails > button#js-testimonialThumbnail1
Testimonial video thumbnail 2 div.content > div.home-testimonial-figure > div.home-testimonial-thumbnails > button#js-testimonialThumbnail2
Testimonial video thumbnail 3 div.content > div.home-testimonial-figure > div.home-testimonial-thumbnails > button#js-testimonialThumbnail3
Testimonial video thumbnail 4 div.content > div.home-testimonial-figure > div.home-testimonial-thumbnails > button#js-testimonialThumbnail4

Labels ensure that form controls are announced properly by assistive technologies, like screen readers. Learn more about form element labels.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.item-text > div.audioPlayer-controls > div.player-bars > input.seek-bar div.item-text > div.audioPlayer-controls > div.player-bars > input.seek-bar

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.

Best practices

Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. Learn more about touch targets.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Play div.inner > div.item-text > div.audioPlayer-controls > button.btn
div.item-text > div.audioPlayer-controls > div.player-bars > input.seek-bar div.item-text > div.audioPlayer-controls > div.player-bars > input.seek-bar
Testimonial video thumbnail 1 div.content > div.home-testimonial-figure > div.home-testimonial-thumbnails > button#js-testimonialThumbnail1
Testimonial video thumbnail 2 div.content > div.home-testimonial-figure > div.home-testimonial-thumbnails > button#js-testimonialThumbnail2
Testimonial video thumbnail 3 div.content > div.home-testimonial-figure > div.home-testimonial-thumbnails > button#js-testimonialThumbnail3
Testimonial video thumbnail 4 div.content > div.home-testimonial-figure > div.home-testimonial-thumbnails > button#js-testimonialThumbnail4

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
●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
●Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
●`[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
●`<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
●Heading elements appear in a sequentially-descending order
●Skip links are focusable.
●Document has a main landmark.
●Deprecated ARIA roles were not used
●Identical links have the same purpose.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements 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.
○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.
○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.
A
Landmark Structure
46 landmarks
PASS
46 landmarks
Info::
<main> landmark present
Info::
4 <nav> landmark(s) found
Warning::
4 of 4 <nav> elements are unlabeled
Multiple navigations need aria-label to distinguish them for screen readers.
Info::
Skip navigation link present
Page Structure — as a screen reader sees it
BANNER header NAV 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+
Heading Hierarchy
30 headings
PASS
30 headings
Info::
Single H1 present
  • H3 Explore Skills
  • H3 Cloud Computing
  • H3 Data Engineering
  • H3 Data Science
  • H3 AI & ML
  • H3 Programming Languages
  • H3 Software Architecture
  • H3 IT/Ops
  • H3 Security
  • H3 Design
  • H3 Business
  • H3 Soft Skills
  • H3 Features
  • H1 Build the skills your teams need
  • H2 From the Radar blog
  • H2 Verifiable skills: Close key gaps and prove your ability
  • H2 Level up with expert-led live courses
  • H2 We share the knowledge of innovators. You put it to work.
  • H2 More than 5,000 organizations count on O’Reilly
  • H2 The 2025 O’Reilly Awards winners are in!
  • H2 Hear why Jose is on O’Reilly every day
  • H2 See why Addison loves our learning platform
  • H2 Amir trusts O’Reilly to find the answers he needs. See why.
  • H2 Mark’s been an O’Reilly member for 13 years. See why.
  • H2 See how O’Reilly can help your tech teams stay ahead
  • H2 About O'Reilly
  • H2 Support
  • H2 International
  • H2 Download the O'Reilly App
  • H2 Watch on Your Big Screen
A+
Alt Text Quality
All 26 images OK
PASS
All 26 images OK
Info::
10 decorative image(s) correctly marked
Info::
16 image(s) with good alt text
26 images 16 good alt text 10 decorative
All images have appropriate alt text.
A
Form Accessibility
1 of 3 controls have issues
PASS
1 of 3 controls have issues
Critical::
1 control(s) without accessible label
Form controls need a <label>, aria-label, or aria-labelledby for screen readers.
Got: <input type="range">
Info::
2 control(s) properly labeled
3 controls
2 labeled
0 placeholder only
1 unlabeled
ControlTypeLabelMethod
qsearchSearch for books, courses, events, and morenone
qsearchSearch for books, courses, events, and morenone
inputrange(none)none

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

<input type="range">

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

A+
Color Contrast (Screenshot)
20 text elements analyzed, 0 fail WCAG AA
PASS

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

20 pass
Show all checked elements (20)
ElementRatioRequiredFGBGResult
h1 Build the skills you…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 From the Radar blog21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Verifiable skills: C…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Level up with21.00:13.0:1
#000000
#FFFFFF
Pass
h2 live courses21.00:13.0:1
#000000
#FFFFFF
Pass
h2 We share the knowled…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 More than 5,000 orga…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 The 2025 O’Reilly …21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Hear why Jose is on …21.00:13.0:1
#000000
#FFFFFF
Pass
h2 See why Addison love…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Amir trusts O’Reil…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Mark’s been an O…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 See how O’Reilly c…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 International21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Download the O'Reill…21.00:13.0:1
#000000
#FFFFFF
Pass
h2 Watch on Your Big Sc…21.00:13.0:1
#000000
#FFFFFF
Pass
h3 Explore Skills21.00:13.0:1
#000000
#FFFFFF
Pass
h3 Cloud Computing21.00:13.0:1
#000000
#FFFFFF
Pass
h3 Data Engineering21.00:13.0:1
#000000
#FFFFFF
Pass
h3 Data Science21.00:13.0:1
#000000
#FFFFFF
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.

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

Send Feedback