Accessibility health score

Every scan run in the platform generates an accessibility health score (or scan score), shown as a number from 0 to 100.

The Portfolio and Overview show scores from your latest monitoring scans, while the Scan results page shows scores from quick and advanced scans.

On this page:

• What is the accessibility health score?
• How can I use it?
• How is it calculated?
• How can I improve it?
• Why is it different for each automated testing tool?

What is the accessibility health score?

The accessibility health score is an indicator of the accessibility of a webpage based on scans run in the platform. On a scale of 0–100, or weak to strong, it shows the degree to which a webpage meets or violates the tested accessibility rules.

Used over time with monitoring, the score can be a measure of relative change. Notice your scores improve as you fix accessibility issues and take action if they start to drop.

Because the score is based only on scans–rather than evaluations and scans–it’s not a complete rating of accessibility. It’s also not a measure of conformance with the WCAG guidelines. If you want to understand a website or app’s overall accessibility based on scans and evaluation results, check the Overview.

How can I use the accessibility health score?

Set up monitoring to use the score as a tool to reach and maintain your accessibility goals.

When you first start out

1. Find out where you stand by running an initial monitoring scan.
   • 0–50: Your accessibility practices are likely still developing. Your team’s not yet focused on fixing the most critical findings.
   • 51–84: You’re likely on the right track to accessible practices, but critical findings are still being introduced.
   • 85–100: Your team is likely making a conscious effort to design and build with accessibility in mind.
     
2. Decide what to remediate first.
   • From the Portfolio, review which of your websites/apps have the lowest scores. Prioritize fixing critical findings from those properties before moving on to others.
3. Start remediating findings to improve your score (and keep a record).
   • To improve your score: fix findings, dismiss false positives, and incorporate accessibility testing into your practices. Find out how far you’ve come by comparing early scores to more recent ones using the Monitoring page.

When you’re more established

1. Manage your accessibility health.
   • Set up monitoring alerts to get an email notification when a score drops below a certain level. Use those alerts to act fast and identify the source of the problem.
2. Change your practices based on long-term trends.
   • The score should increase as you fix code-level accessibility issues. If it starts trending down, look into your release practices and find where accessibility issues are being overlooked.
3. Set thresholds for end-to-end testing.
   • Add our APIs to your development process to view scores before you deploy. Choose to deploy only when your build passes a certain score. That way, you won’t introduce critical findings into the code.

How is the accessibility health score calculated?

The accessibility health score is a weighted score calculated for each webpage in a scan. For multi-page scans, it’s an average across all pages.

The score takes the following into account:

• The total number of rules that passed and failed during the scan (not the total number of findings).
• The total number of recommendations that passed and failed during the scan.
• The severity of the rules and recommendations that failed during the scan. Critical or high severity levels have a larger negative impact on your score than low severity levels.

How can I improve my accessibility health score?

The accessibility health score is a long-term metric that requires consistent remediation across the scanned pages to achieve lasting score improvements. If you want to start improving your score, there are many variables to consider:

• The number of pages in your scan
• Scan scores by page
• Severity of the rules

Here are some tips to improve your accessibility health score:

• Take a comprehensive approach. Scores are based on several factors, including the number of pages and severity of rule violations. For multi-page scans, addressing critical issues across multiple pages may help improve your score.
• For each page, fix all findings in a failed rule and dismiss false positives. There won't be any improvement from fixing one out of many findings in a rule.
• Prioritize critical and high severity findings. Critical and high severity findings have a bigger impact than low severity findings.

To maintain your health score, it's important to consider the types of findings and address the root of the issue. For example, if most of your findings are contrast issues, focus on retraining your design team on accessible design.

Why is the accessibility health score different for each automated testing tool?

Every scan collects data from four different testing tools: Access Engine, equal-access, WAVE, and axe-core. If you check the same set of scan results with different tools, you’ll notice that each tool shows a different score.

Each testing tool has a unique library of rules that it tests against during a scan. Because the score is calculated based on the number of rules tested and the severity of the rules that were violated, the scan results, including the accessibility health score, will never be identical between tools.

Use one tool consistently to utilize the benefits of the accessibility health score.