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Accessibility

· 13 checks — Landmarks, headings, alt text, forms, and link quality rolled into one auditable list.
SCORE
63
GRADE
D
FIX
4
REVIEW
4
PASS
5
INFO
0
Checks
13
5 PASS 4 REVIEW 4 FIX
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::
2 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 2 <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.
B
404 Error Page
HTTP 404, custom page
REVIEW
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
404 Page Quality ✓ Custom 404 Page
Status Code HTTP 404 ✓Page Title 国立国会図書館 ✓Custom Styling ✓Navigation ✓Homepage Link ✓Search Form ✗
C
Favicon & Branding
Action
3 icon(s) detected
REVIEW
3 icon(s) detected
Info::
favicon.ico present at site root
Info::
HTML icon links detected
Info::
Apple touch icon present
✓ favicon.ico Present
✓ PNG Icons Present
✓ Apple Touch Present
✗ SVG Favicon Missing
✗ Manifest Icons Missing
✗ Multiple Sizes Missing
B
Lighthouse Accessibility Audits
Score 85/100 — 5 failing, 23 passed
REVIEW
85

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.base-layout-column > div.base-layout-column > a > button.base-button div.base-layout-column > div.base-layout-column > a > button.base-button
div.base-layout-column > div.base-layout-column > a > button.base-button div.base-layout-column > div.base-layout-column > a > button.base-button
div.base-layout-column > div.base-layout-column > a > button.base-button div.base-layout-column > div.base-layout-column > a > button.base-button

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.base-panel > div.base-layout-column > div.base-layout-row > a.lang-link div.base-panel > div.base-layout-column > div.base-layout-row > a.lang-link

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
X div.base-layout-column > ul.base-layout-row > li.base-layout-column > ul.base-layout-column

Screen readers require list items (`<li>`) to be contained within a parent `<ul>`, `<ol>` or `<menu>` to be announced properly. Learn more about proper list structure.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
X li.base-layout-column > ul.base-layout-column > div.base-layout-row > li.base-layout-column
YouTube li.base-layout-column > ul.base-layout-column > div.base-layout-row > li.base-layout-column

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

Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
もっと見る div.base-layout-container > div.base-layout-container-inner > div.base-layout-column > button.base-button
○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
●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
●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
●No element has a `[tabindex]` value greater than 0
●Touch targets have sufficient size and spacing.
●Heading elements appear in a sequentially-descending order
●Document has a main landmark.
●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 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
○Links are distinguishable without relying on color.
○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.
○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
5 landmarks
PASS
5 landmarks
Info::
<main> landmark present
Info::
2 <nav> landmark(s) found
Info::
All <nav> elements are properly labeled
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 "サイトメニュー" 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
11 headings
PASS
11 headings
Warning::
Multiple H1 headings (2 found)
A page should have only one H1. Multiple H1s dilute the document outline.
  • H1 国立国会図書館
  • H1 国立国会図書館 duplicate H1
  • H2 重要なお知らせ
  • H2 資料を検索
  • H2 ピックアップ
  • H2 おしらせ RSS
  • H2 来館案内
  • H3 東京本館
  • H3 関西館
  • H3 国際子ども図書館
  • H3 国立国会図書館でのクッキーの使用

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

A
Alt Text Quality
1 of 9 images have issues
PASS
1 of 9 images have issues
Warning::
1 image(s) with generic alt text
Info::
3 image(s) with alt text over 125 characters
Info::
5 image(s) with good alt text
9 images 5 good alt text 1 generic
IssueCount
generic1 image(s)
too long3 image(s)
A
Form Accessibility
1 of 3 controls have issues
PASS
1 of 3 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="search" id="hp-top-search">
Info::
2 control(s) properly labeled
3 controls
2 labeled
1 placeholder only
0 unlabeled
ControlTypeLabelMethod
#h-search-selectselect検索対象aria-label
#h-searchsearch検索キーワードaria-label
#hp-top-searchsearch(資料を検索)placeholder only

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

<input type="search" id="hp-top-search">

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+
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
h2 重要なお知ら…15.17:13.0:1
#000000
#DBDBDB
Pass
h2 資料を検索15.17:13.0:1
#000000
#DBDBDB
Pass
h2 ピックアップ15.17:13.0:1
#000000
#DBDBDB
Pass
h2 おしらせ15.17:13.0:1
#000000
#DBDBDB
Pass
h2 来館案内15.17:13.0:1
#000000
#DBDBDB
Pass
h3 東京本館15.17:13.0:1
#000000
#DBDBDB
Pass
h3 関西館15.17:13.0:1
#000000
#DBDBDB
Pass
h3 国際子ども図…15.17:13.0:1
#000000
#DBDBDB
Pass
h3 国立国会図書…15.17:13.0:1
#000000
#DBDBDB
Pass
title 国立国会図書…21.00:14.5:1
#000000
#FFFFFF
Pass
a 本文へ移動20.62:14.5:1
#000000
#FCFDFE
Pass
option サイト内20.16:14.5:1
#000000
#F7FBFC
Pass
option 資料20.16:14.5:1
#000000
#F7FBFC
Pass
span 検索20.16:14.5:1
#000000
#F7FBFC
Pass
span ヘルプ20.16:14.5:1
#000000
#F7FBFC
Pass
button English20.16:14.5:1
#000000
#F7FBFC
Pass
a ホーム20.16:14.5:1
#000000
#F7FBFC
Pass
button 国会関連情報20.16:14.5:1
#000000
#F7FBFC
Pass
button 資料・情報の…20.16:14.5:1
#000000
#F7FBFC
Pass
button 来館案内20.16:14.5:1
#000000
#F7FBFC
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.

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