Does fixing HTML accessibility errors guarantee WCAG compliance?

No. HTML validation catches structural accessibility errors. Full WCAG compliance requires testing with real assistive technologies and evaluating visual design, color contrast, and interaction patterns — beyond what HTML validation covers.

What HTML errors most commonly cause accessibility failures?

Missing alt attributes on images, unlabelled form inputs, incorrect heading hierarchy, and missing `lang` attribute on the ` ` element are the most frequent HTML-level accessibility failures. Fixing these covers the majority of WCAG 2.1 Level A requirements.

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Check HTML for Accessibility Issues

Accessible HTML is not just good practice — it is often a legal requirement. FixTools checks your HTML for common accessibility issues: missing alt text, unlabelled form inputs, incorrect ARIA usage, and semantic structure problems.

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Checks for missing alt attributes

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Identifies unlabelled form inputs

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Validates ARIA role usage

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How to use this tool

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Paste your HTML and validate. Accessibility-related errors are flagged alongside standard HTML errors.

How It Works

Step-by-step guide to check html for accessibility issues:

1
Paste your HTML
Paste the HTML page or component you want to check for accessibility.
2
Validate
Click Validate. Accessibility-related errors are flagged in the results.
3
Fix accessibility errors first
Prioritise missing alt text, unlabelled inputs, and ARIA errors above structural formatting issues.
4
Re-validate
Confirm all accessibility errors are resolved.

Real-world examples

Common situations where this approach makes a real difference:

Pre-audit HTML accessibility review

Before a formal WCAG audit, check HTML for the most common accessibility violations to maximise the value of the auditor's time.

Checking a client website for accessibility compliance

When conducting a website audit for a client, run all HTML through the accessibility checker to produce a baseline list of structural issues to address.

When to use this guide

Use this during development and before deployment to catch accessibility errors that would fail a WCAG audit or screen reader test.

Pro tips

Get better results with these expert suggestions:

Alt text is mandatory for all images

Every <img> element requires an alt attribute. For informative images, describe the content. For decorative images, use alt="" (empty string).

ARIA roles supplement, not replace, semantic HTML

Use semantic HTML elements first (nav, button, main). Only add ARIA roles when native elements cannot convey the correct meaning.

Test with a screen reader after fixing

After fixing HTML accessibility errors identified by the validator, test the page with a screen reader (NVDA, VoiceOver, JAWS) to confirm the experience is correct.