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Accessibility

· 13 checks — Landmarks, headings, alt text, forms, and link quality rolled into one auditable list.
SCORE
71
GRADE
C
FIX
3
REVIEW
4
PASS
6
INFO
0
Checks
13
6 PASS 4 REVIEW 3 FIX
D
Dark Mode Support
Action
Theme color only
FIX
Theme color only
Info::
Theme-color present but no dark variant
A theme-color is set but no dark-specific variant was found. The browser toolbar may not adapt for dark mode users.
Got: #fbf0df
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 ModePartial Dark Mode
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::
1 navigation landmark(s) detected
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 1 <nav> element(s)
Back to Top
Hamburger Menu
Sticky Navigation Cannot reliably detect (CSS-based)
1 of 6 testable patterns navigation patterns detected. Limited navigation support. Consider adding breadcrumbs, search, and skip link.
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
404 Page Quality ✓ Custom 404 Page
Status Code HTTP 404 ✓Page Title Page not found — Bun ✓Custom Styling ✓Navigation ✗Homepage Link ✗Search Form ✗
C
Color Contrast (Screenshot)
Action
20 text elements analyzed, 20 fail WCAG AA
REVIEW

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

0 pass 20 fail WCAG AA
h1 Bun is a
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
32px · bottom of viewport
h1 JavaScript
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
32px · bottom of viewport
h2 Bundling 10,000 React components
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Express.js 'hello world'
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 WebSocket chat server
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Load a huge table
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Four tools, one toolkit
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Who uses Bun?
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 What's different about Bun?
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Everything you need to build & ship
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Bun is a JavaScript runtime.
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Bun works with Next.js
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Full speed full-stack
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Bun is an npm-compatible package manager…
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Bun is a test runner that makes the rest…
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 The APIs you need. Baked in.
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Learn more
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h2 Developers love Bun.
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
24px · bottom of viewport
h3 JavaScript Runtime
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
19px · bottom of viewport
h3 Package Manager
1.15:1
#000000
on
#16141A
needs 3.0:1 (large text)
19px · bottom of viewport
Show all checked elements (20)
ElementRatioRequiredFGBGResult
h1 Bun is a1.15:13.0:1
#000000
#16141A
Fail
h1 JavaScript1.15:13.0:1
#000000
#16141A
Fail
h2 Bundling 10,000 Reac…1.15:13.0:1
#000000
#16141A
Fail
h2 Express.js 'hello wo…1.15:13.0:1
#000000
#16141A
Fail
h2 WebSocket chat serve…1.15:13.0:1
#000000
#16141A
Fail
h2 Load a huge table1.15:13.0:1
#000000
#16141A
Fail
h2 Four tools, one tool…1.15:13.0:1
#000000
#16141A
Fail
h2 Who uses Bun?1.15:13.0:1
#000000
#16141A
Fail
h2 What's different abo…1.15:13.0:1
#000000
#16141A
Fail
h2 Everything you need …1.15:13.0:1
#000000
#16141A
Fail
h2 Bun is a JavaScript …1.15:13.0:1
#000000
#16141A
Fail
h2 Bun works with Next.…1.15:13.0:1
#000000
#16141A
Fail
h2 Full speed full-stac…1.15:13.0:1
#000000
#16141A
Fail
h2 Bun is an npm-compat…1.15:13.0:1
#000000
#16141A
Fail
h2 Bun is a test runner…1.15:13.0:1
#000000
#16141A
Fail
h2 The APIs you need. B…1.15:13.0:1
#000000
#16141A
Fail
h2 Learn more1.15:13.0:1
#000000
#16141A
Fail
h2 Developers love Bun.1.15:13.0:1
#000000
#16141A
Fail
h3 JavaScript Runtime1.15:13.0:1
#000000
#16141A
Fail
h3 Package Manager1.15:13.0:1
#000000
#16141A
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.

B
Lighthouse Accessibility Audits
Score 84/100 — 5 failing, 28 passed
REVIEW
84

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.mt-6 > div.overflow-hidden > div.flex > button#dVjQXKqEuFBK:copy div.mt-6 > div.overflow-hidden > div.flex > button#dVjQXKqEuFBK:copy
section.dark > div.overflow-hidden > div.flex > button#YPBCdturNXaQ:copy section.dark > div.overflow-hidden > div.flex > button#YPBCdturNXaQ:copy

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
main.mx-auto > div.flex-1 > div.pointer-events-none > img.mt-4 main.mx-auto > div.flex-1 > div.pointer-events-none > img.mt-4

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.flex > div.text-lg > div.flex > a div.flex > div.text-lg > div.flex > a

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.

Tables and lists

Screen readers have a specific way of announcing lists. Ensuring proper list structure aids screen reader output. Learn more about proper list structure.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Build Docs Reference Guides Blog Discord div.dark > header.w-screen-xl > div#default-slider-menu-menu > ul.m-auto

These are opportunities to improve the experience of reading tabular or list data using assistive technology, like a screen reader.

Screen readers have features to make navigating tables easier. Ensuring that `<td>` elements in a large table (3 or more cells in width and height) have an associated table header may improve the experience for screen reader users. Learn more about table headers.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Builtin Core Features Bun Node Node.js compatibility Web Standard … body.min-h-[100vh] > section.dark > div.w-min-content > table.border-collapse
○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
●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
●`[aria-*]` attributes have valid values
●`[aria-*]` attributes are valid and not misspelled
●`[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.
●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.
●Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
●Heading elements appear in a sequentially-descending order
●Document has a main landmark.
●Deprecated ARIA roles were not used
●`<video>` elements contain a `<track>` element with `[kind="captions"]`
●Image elements do not have `[alt]` attributes that are redundant text.
●Identical links have the same purpose.
●Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
○`[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 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.
○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
○`[lang]` attributes have a valid value
○Tables have different content in the summary attribute and `<caption>`.
○All heading elements contain content.
○Uses ARIA roles only on compatible elements
○Elements with visible text labels have matching accessible names.
A
Landmark Structure
10 landmarks
PASS
10 landmarks
Info::
<main> landmark present
Info::
1 <nav> landmark(s) 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 NAV MAIN CONTENTINFO footer

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

A+
Heading Hierarchy
45 headings
PASS
45 headings
Info::
Single H1 present
  • H1 Bun is a fast JavaScriptall-in-one toolkit|
  • H2 Bundling 10,000 React components
  • H2 Express.js 'hello world'
  • H2 WebSocket chat server
  • H2 Load a huge table
  • H2 Four tools, one toolkit
  • H3 JavaScript Runtime
  • H3 Package Manager
  • H3 Test Runner
  • H3 Bundler
  • H2 Who uses Bun?
  • H3 Claude Code uses Bun
  • H3 Railway Functions powered by Bun
  • H3 Midjourney uses Bun
  • H2 What's different about Bun?
  • H3 Builtin Core Features
  • H3 Builtin APIs
  • H3 Builtin Tooling
  • H3 Builtin Utilities
  • H2 Everything you need to build & ship
  • H3 HTTP & WebSockets
  • H3 Databases
  • H3 File System
  • H3 Testing
  • H3 Build & Deploy
  • H3 TypeScript & DX
  • H3 Security
  • H3 System Integration
  • H3 Utilities
  • H2 Bun is a JavaScript runtime.
  • H2 Bun works with Next.js
  • H3 Lee Robinson
  • H2 Full speed full-stack
  • H3 Develop and ship frontend apps
  • H4 Start a dev server
  • H4 Hot Module Replacement
  • H4 Build for production
  • H2 Bun is an npm-compatible package manager.
  • H2 Bun is a test runner that makes the rest look like test walkers.
  • H2 The APIs you need. Baked in.
  • H2 Learn more
  • H3 Documentation
  • H3 API Reference
  • H2 Developers love Bun.
  • H3 Popular Questions
A
Alt Text Quality
1 of 25 images have issues
PASS
1 of 25 images have issues
Critical::
1 image(s) missing alt attribute
Images without alt text are invisible to screen readers.
Info::
24 image(s) with good alt text
25 images 24 good alt text 1 missing
IssueCount
missing1 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

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: <textarea>
1 controls
0 labeled
1 placeholder only
0 unlabeled
ControlTypeLabelMethod
textareatextarea(How do I get started?)placeholder only

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

<textarea>

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
Favicon & Branding
18 icon(s) detected
PASS
18 icon(s) detected
Info::
favicon.ico present at site root
Info::
HTML icon links detected
Info::
Apple touch icon present
Info::
SVG favicon detected — scales perfectly to any size
Info::
Multiple icon sizes detected
✓ favicon.ico Present
✓ PNG Icons Present
✓ Apple Touch Present
✓ SVG Favicon Present
✓ Manifest Icons Present
✓ Multiple Sizes Present
A+
Web Manifest
PWA-ready
PASS
PWA-ready
Info::
Meets PWA install criteria
Info::
Name present: Bun
Info::
192x192 icon present
Info::
512x512 icon present
Info::
Display mode: minimal-ui
PWA Install Criteria ✓ Installable
Name Bun ✓192×192 icon ✓512×512 icon ✓Start URL / ✓Display Mode minimal-ui ✓
Name Bun Display Mode minimal-ui Theme Color #fbf0df Background Color #fbf0df Icons 7 icon(s)
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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