Accessibility Audit: A Complete Guide

What is an accessibility audit?

An accessibility audit is a review of your website or digital product. The goal is simple: find barriers that stop people with disabilities from using your site.

An audit checks your site against established standards. The most common standard is WCAG 2.1 Level AA — the same standard referenced by the European Accessibility Act and most other accessibility laws.

A good audit answers three questions:

1. Where are the barriers? — Which pages and elements fail the standards?
2. How bad are they? — Which issues block users completely, and which cause minor frustration?
3. How do you fix them? — What specific changes are needed?

Why audit your website?

Legal requirements

Since 28 June 2025, the European Accessibility Act (Directive 2019/882) requires many digital products and services to be accessible. In the UK, the Equality Act 2010 and the Public Sector Bodies Accessibility Regulations 2018 set accessibility requirements for public sector organisations.

An audit is the first step to understanding where you stand.

The scale of the problem

The WebAIM Million study — an annual analysis of the top 1,000,000 home pages — consistently finds that over 96% of home pages have detectable WCAG failures. The most common issues are the same year after year: low contrast text, missing alt text, empty links, missing form labels, and missing document language.

These are not niche issues. They affect real users every day. An estimated 16% of the global population has a significant disability (World Health Organization, 2023).

Types of accessibility audits

Automated scanning

Automated tools crawl your website and check each page against WCAG success criteria that can be tested programmatically.

What automated tools reliably detect:

• Missing alternative text on images (SC 1.1.1)
• Insufficient colour contrast (SC 1.4.3)
• Missing form labels (SC 1.3.1)
• Missing document language (SC 3.1.1)
• Empty links and buttons (SC 4.1.2)
• Missing page titles (SC 2.4.2)

What automated tools cannot detect:

• Whether alt text is actually meaningful (not just present)
• Whether keyboard navigation order makes sense
• Whether screen reader announcements are helpful
• Whether a heading structure is logical
• Whether custom interactive components work with assistive technology

Research by the UK Government Digital Service and academic studies consistently show automated tools detect roughly 30-40% of WCAG issues. The rest requires human judgement.

Start with a free scan: Check your website with Askem — no signup needed, results in about 60 seconds.

Manual expert audit

A manual audit is done by a trained accessibility specialist. They use assistive technologies — screen readers like NVDA (free, Windows) or VoiceOver (built into macOS/iOS) — and their knowledge of WCAG success criteria to find issues that tools miss.

Manual testing is especially important for:

• Custom interactive components (date pickers, carousels, modals)
• Complex forms with validation
• Single-page applications and dynamic content
• Video players and media content

Combined approach (recommended)

The most effective approach combines automated scanning for broad, continuous coverage with manual testing for depth. Use automated monitoring to catch regressions in real time, and schedule manual audits for key user journeys.

Step-by-step audit process

1. Define scope

You cannot audit every page at once on a large site. Prioritise:

• Homepage — the most visited page and the first impression
• Key user journeys — the paths users follow to complete tasks (signup, purchase, contact, booking)
• Content templates — one of each page type (blog post, product page, landing page) since template-level fixes benefit all pages using that template
• High-traffic pages — use your analytics to identify the pages that matter most

2. Run automated scans

Scan your site with automated tools. Askem's free accessibility checker scans your pages and reports issues grouped by severity and WCAG success criterion.

Review the results and group issues into:

• Template-level issues — problems in your header, footer, navigation, or page templates that appear on every page
• Content-level issues — problems in specific pages (missing alt text on a particular image, for example)

Fix template-level issues first — one fix can resolve hundreds of failures across your site.

3. Keyboard testing

Navigate your website using only the keyboard. Do not touch the mouse. Use these keys:

Key	Action
Tab	Move to the next interactive element
Shift + Tab	Move to the previous interactive element
Enter	Activate a link or button
Space	Activate a button or toggle a checkbox
Arrow keys	Navigate within menus, radio groups, tabs
Escape	Close a modal or dropdown

Check for these common failures:

• Keyboard traps — Can you get stuck in a component with no way to Tab out?
• Missing focus indicators — Can you see where focus is at all times?
• Unreachable elements — Are there interactive elements you cannot reach by Tab?
• Illogical tab order — Does focus move in a sensible order through the page?
• Inoperable components — Can you open and close all menus, modals, and dropdowns?

4. Screen reader testing

Test with at least one screen reader:

Screen reader	Platform	Cost
NVDA	Windows	Free
VoiceOver	macOS / iOS	Built in
JAWS	Windows	Licensed
TalkBack	Android	Built in

While using the screen reader, check:

• Are images announced with meaningful descriptions?
• Are form fields announced with their labels?
• Do headings create a logical document outline?
• Are error messages and status changes announced?
• Can you understand and operate all interactive components?

5. Document findings

For each issue found, record:

• WCAG success criterion — which specific criterion fails (e.g., SC 1.4.3 Contrast Minimum)
• Severity — Critical (blocks access), Major (significantly impairs use), or Minor (causes inconvenience)
• Location — URL and element (with a screenshot if helpful)
• How to fix it — specific remediation steps

The most common accessibility issues

The WebAIM Million 2024 report analysed 1,000,000 home pages. The top failures found:

Issue	% of pages affected	WCAG criterion
Low contrast text	81.0%	1.4.3 Contrast (Minimum)
Missing image alt text	54.5%	1.1.1 Non-text Content
Empty links	48.6%	4.1.2 Name, Role, Value
Missing form input labels	45.0%	1.3.1 Info and Relationships
Empty buttons	28.2%	4.1.2 Name, Role, Value
Missing document language	17.1%	3.1.1 Language of Page

Source: WebAIM Million 2024

These issues are straightforward to detect with automated tools and straightforward to fix. If your site has these problems, an automated scan is the fastest path to improvement.

Accessibility audit checklist

Use this checklist as a starting point. It covers the most common and impactful WCAG 2.1 AA criteria:

Images and media

• All informative images have descriptive alt text
• Decorative images have empty alt attributes (alt="")
• Videos have captions
• Audio content has transcripts

Text and colour

• Normal text has a contrast ratio of at least 4.5:1
• Large text (18pt+) has a contrast ratio of at least 3:1
• Information is not conveyed by colour alone
• Text can be resized to 200% without loss of content

Navigation and keyboard

• All interactive elements are reachable by keyboard
• Focus order is logical
• Focus indicators are visible
• No keyboard traps
• Skip navigation link is present

Forms

• All form inputs have associated labels
• Required fields are indicated
• Error messages identify the field and describe the error
• Error suggestions are provided where possible

Structure

• Page has a descriptive title
• Headings are in a logical hierarchy (H1 → H2 → H3)
• Page language is declared in the HTML
• Landmarks are used (header, nav, main, footer)

When is an accessibility audit legally required?

Under the European Accessibility Act, organisations covered by the directive must be able to demonstrate conformity with the accessibility requirements from 28 June 2025. While the directive does not mandate a specific audit, you need to:

• Maintain technical documentation showing how requirements are met
• Respond to requests from market surveillance authorities

In the UK, public sector bodies must publish an accessibility statement describing their site's accessibility status and known issues. An audit is the practical way to produce this statement.

For most organisations, an accessibility audit is the most defensible way to demonstrate compliance — whether or not one is explicitly required by law.

Check your website now

Run a free accessibility scan with Askem to see your site's WCAG compliance status. No signup, no payment — just enter your URL and get results in about 60 seconds.

For ongoing compliance, Askem provides continuous monitoring that catches new issues whenever your site changes — so you do not have to wait for the next annual audit to discover a problem.

Further reading

• WCAG 2.1 specification (W3C)
• WCAG 2.1 Quick Reference — filterable checklist (W3C)
• WebAIM Million — annual accessibility analysis
• Understanding WCAG success criteria (W3C WAI)
• European Accessibility Act — complete guide
• WCAG 2.2 — what's new