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Website Accessibility Checker

Enter a URL or paste HTML to find WCAG failures: images without alt text, unlabeled form fields, empty links and buttons, heading order and ARIA errors. Free, no sign-up.

This checker reads the markup, so it cannot measure color contrast. For that, use the Color Contrast Checker with your text and background colors.

Check Every Page, Not One

Most free accessibility checkers, this one included, test the page in front of them. A site is not one page: a missing form label in a template repeats on every page built from it, and a fix on the home page says nothing about the product pages.

The website accessibility audit reads every page of a site in one run. It is free and gives you the score, the totals and the five issues to fix first; the complete report lists every page with its own findings, grouped by WCAG success criterion, so a template fault reads as one fix rather than a hundred. The most useful moment to run it is before a launch or a redesign goes live.

Common Accessibility Issues This Checker Finds

Missing Alt Attributes

error

Every <img> element must have an alt attribute describing the image content. Screen readers rely on this text to convey image meaning.

Incorrect Heading Hierarchy

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Headings should follow a logical order (h1 → h2 → h3). Skipping levels makes it harder for screen reader users to navigate.

Missing Form Labels

error

Form inputs must have associated <label> elements or aria-label attributes for screen reader users.

Missing Language Attribute

warning

The <html> element should include a lang attribute to help screen readers pronounce content correctly.

Empty Links and Buttons

error

Links and buttons must have discernible text. Icon-only buttons need aria-label attributes.

Missing Document Title

error

Every page needs a <title> element. It is the first thing announced by screen readers.

Why Web Accessibility Matters

Web accessibility ensures that websites are usable by everyone, including people with disabilities. Over 1 billion people worldwide live with some form of disability.

Beyond the ethical case, accessibility is a legal requirement for many sites: Section 508 for US federal agencies, the Americans with Disabilities Act (ADA) in US website lawsuits, and the European Accessibility Act for many consumer services in the EU since June 2025. WCAG is the standard they point to.

Accessible HTML also improves SEO. Search engines use similar signals to screen readers: clear heading hierarchy, descriptive alt text, and semantic markup all help search engines understand your content better.

This checker tests one page, once. If you look after a site that keeps changing, or you deliver to a client who wants a document, we also offer paid accessibility monitoring: a whole site audited, then re-scanned every week so a regression reaches you before it reaches them.

Frequently Asked Questions

What is web accessibility?
Web accessibility means designing and building websites that can be used by everyone, including people with visual, auditory, motor, or cognitive disabilities. This includes users who rely on screen readers, keyboard navigation, voice control, or other assistive technologies. Accessible websites follow standards like WCAG to ensure equal access to information and functionality.
What is WCAG and which version should I follow?
WCAG (Web Content Accessibility Guidelines) is the international standard for web accessibility, published by the W3C. Accessibility laws such as Section 508 in the US and the European Accessibility Act build on it. WCAG 2.1 Level AA is the level most laws and audits use; WCAG 2.2, published in 2023, adds nine criteria on top. Target 2.1 AA as a minimum and 2.2 AA where you can.
How is this checker different from WAVE, axe or Lighthouse?
WAVE, axe DevTools and Lighthouse test one page at a time. This checker tests a page by URL or pasted code, so it also works on HTML that is not deployed yet, and the whole-site scan reads every page of a site in one run, which is what you need before a launch or a redesign. The rules are aligned with axe-core conventions, so results line up with the tools your developers already use.
Will this checker make my site ADA or EAA compliant?
No, and no automated tool can. Automated rules catch a real share of accessibility issues: about 57% of issues by volume in Deque's study of 13,000 pages, but only 16 of the 50 WCAG 2.1 AA success criteria, because many criteria need a human (meaningful alt text, keyboard flow, captions). Use this checker to find and fix what machines can find, then test the rest by hand or with an auditor before claiming conformance.
What are ARIA labels and when should I use them?
ARIA (Accessible Rich Internet Applications) labels provide additional context to assistive technologies when native HTML semantics are not sufficient. Use aria-label to name interactive elements like icon-only buttons, aria-describedby to link descriptions, and role attributes to define custom widget behavior. However, prefer native HTML elements over ARIA when possible. A <button> is better than <div role="button">.
Why does accessibility matter for SEO?
Accessibility and SEO share many overlapping best practices. Search engines rely on similar signals to screen readers: clear heading hierarchy, descriptive alt text, semantic HTML, proper link text, and logical page structure. Improving accessibility almost always improves SEO, as it makes your content more understandable to both machines and humans.
Is this accessibility checker free?
Yes. Checking a page by URL or pasted code is free and unlimited, with no sign-up. Scanning a whole site is free too: you get the score, the totals and the five issues to fix first. The complete report of every page comes with a plan, which you can try free for 7 days and which re-scans your sites every week.