Accessibility Benchmarking
What is accessibility benchmarking and how do you compare compliance across sites?
What is accessibility benchmarking?
Accessibility benchmarking is the practice of measuring and comparing WCAG compliance metrics across multiple websites to establish baselines, track progress, and identify competitive gaps. Rather than auditing a single site in isolation, benchmarking uses normalized metrics like errors per page and health scores to make fair comparisons between sites of different sizes. A site with 50 accessibility errors across 500 pages (0.1 errors/page) is performing better than one with 20 errors across 10 pages (2.0 errors/page).
Accessibility benchmarking is the practice of comparing WCAG compliance metrics across multiple websites using normalized measures like errors per page and health scores, enabling fair comparisons regardless of site size and establishing baselines for tracking remediation progress.
Why does accessibility benchmarking matter?
Raw error counts are misleading without context. A large e-commerce site will naturally surface more issues than a 5-page brochure site, but that does not mean it is less accessible. Benchmarking normalizes these numbers so teams can set realistic targets, prioritize fixes against industry peers, and demonstrate measurable improvement to stakeholders. Organizations that benchmark accessibility see faster remediation because the data creates clear, comparable goals.
96.3% of home pages had detected WCAG 2 failures, with an average of 56.8 errors per page across the top 1 million websites.
Organizations that track accessibility metrics over time remediate issues 60% faster than those that perform only one-time audits.
How to fix it
- Run accessibility scans (using axe-core or similar tools) across your own sites and key competitor sites to collect baseline error counts, warning counts, and pages scanned.
- Calculate errors per page (total errors divided by pages scanned) to normalize for site size differences when comparing results.
- Compute a health score using the formula: 100 minus 3 points per error-per-page minus 1 point per warning-per-page, clamped between 0 and 100.
- Break down issues by severity — critical and high severity issues are counted as errors, medium as warnings, and low as informational — to prioritize the most impactful fixes.
- Track scores over time by running repeated scans and comparing results to confirm that fixes are reducing your error rate rather than just shifting issues between categories.
Bad seed, good seed.
<!-- Reporting only raw counts --><p>Site A: 150 errors. Site B: 30 errors.</p><!-- Misleading: Site A has 5,000 pages, Site B has 10 pages --><!-- Normalized comparison --><table><tr><th>Site</th><th>Errors</th><th>Pages</th><th>Errors/Page</th><th>Score</th></tr><tr><td>Site A</td><td>150</td><td>5000</td><td>0.03</td><td>99</td></tr><tr><td>Site B</td><td>30</td><td>10</td><td>3.0</td><td>91</td></tr></table>Frequently asked questions
Why are raw accessibility error counts misleading?
A 5,000-page site will naturally surface more total errors than a 10-page site, even if the larger site is better maintained. Normalizing by pages scanned (errors per page) gives a fair comparison regardless of site size.
How is the accessibility health score calculated?
The health score starts at 100, subtracts 3 points for each error per page and 1 point for each warning per page, and is clamped between 0 and 100. A score of 80 or above is considered good, 50-79 needs attention, and below 50 is critical.
How often should I benchmark accessibility?
Run benchmarking scans at least monthly, or after every major site update or content deployment. Tracking trends over the last 5 scans reveals whether your remediation efforts are working or if new issues are being introduced faster than old ones are fixed.
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