Automated Accessibility Testing: A Practical Guide

Automated accessibility testing helps teams quickly identify common issues that may create barriers or challenges for users with disabilities, including those who rely on screen readers or other assistive technologies.

Key insights

• Automated scanning tools rapidly detect common violations of accessibility standards, like the Web Content Accessibility Guidelines (WCAG).
• Key benefits of automated testing include efficiency, scalability, and consistency.
• There are many different types of tools for automated testing, including browser extensions, CI/CD integrations, and monitoring dashboards.
• While valuable, automation cannot detect all issues: supplementing automation with manual testing by experts and users with disabilities is necessary to validate accessibility compliance and deliver inclusive web content.

What is automated accessibility testing?

Automated accessibility testing tools crawl user flows, web pages, and entire sites, identifying violations of the Web Content Accessibility Guidelines (WCAG) and / or other standards. These automated checks are helpful for surfacing common issues such as missing alt text, insufficient color contrast, links with non-descriptive text, and empty links.

However, while automated testing tools excel at speed and consistency, they cannot detect all errors. Manual evaluation by accessibility experts is essential to validate automated tools’ findings and identify issues that these tools miss. Manual accessibility audits and user testing are especially important for issues requiring context and judgment: for example, only manual experts can determine whether alt text is meaningful or whether interactive elements behave correctly with assistive technologies. Both automated scans and manual evaluation are integral parts of an accessibility program.

Automated testing vs. manual evaluation

Factor	Automated	Manual
Speed	Instant scans	Slower, human-paced
Coverage	Common, machine-detectable accessibility issues	Comprehensive review
Scale	Easy to scale across large websites	Typically limited to core pages, representative pages and components, and user flows
Cost range	Free to low	Higher, scope-dependent
Consistency	Uniform rules	Potentially subject to human biases
Context understanding (e.g., ability to perform tests that rely on context)	Limited	Strong
Best use case	Continuous monitoring	Validating compliance and usability for people with disabilities

 

Benefits of automated accessibility checks

Automated accessibility testing delivers measurable advantages for organizations aiming to improve digital accessibility while managing costs and resources effectively. While manual testing support is essential, accessibility automation provides speed, scale, and consistency that manual assessments alone cannot match. Let’s explore some of the key advantages of automated testing.

1. Speed and scale

Automated accessibility testing solutions can scan hundreds of web pages per minute against specific accessibility standards, identifying issues such as missing alt text, poor color contrast, and empty links. This makes them essential for benchmarking the accessibility of large websites and applications where testing every page manually would be impractical.

2. Cost savings

Automated scans are less resource-intensive than manual accessibility audits. By leveraging automation to surface common accessibility violations, teams can reserve manual evaluations for areas where comprehensive review is critical, such as high-traffic pages, core user flows (like checkout functionality), and widely used components. The ability to run multiple tests at a low cost ensures teams manage accessibility budgets efficiently.

Additionally, certain automated tools enable developers to test code for accessibility issues before production begins. For example, teams can integrate automated checks into CI/CD pipelines, ensuring that every new commit or release is tested against accessibility standards. Proactive testing reduces remediation costs significantly, because fixing issues during development is far cheaper than correcting them after launch.

3. Continuous monitoring

One common use case for automated accessibility checks is ongoing monitoring. Monitoring tools run automated scans at regularly scheduled intervals, providing continuous insight on the accessibility of a page, site, or collection of digital assets. Through monitoring, teams can track remediation progress without much manual effort and ensure that accessibility compliance keeps pace with content updates and feature deployments. Some accessibility platforms with monitoring capabilities also generate detailed reports, which can help teams demonstrate impact to stakeholders.

4. Consistency across tests

While different tools may yield different results, the same automated testing tool will apply web accessibility rules uniformly, reducing variability in test execution. In contrast, manual accessibility test results may be influenced by an individual tester’s knowledge or interpretation.

What automated accessibility testing tools can and cannot detect

Automated testing is a staple of any scalable accessibility program. However, automated tools have their limitations. While they reliably catch structural accessibility defects, they tend to miss contextual violations. They may also catch false positives that should be verified through manual testing.

The following tables provide examples of the types of issues that can be detected through automation, and those that require manual review by an expert, along with the relevant WCAG success criteria.

Examples of issues that can be detected through automation

Issue type	WCAG criterion	Example
Missing alt text	1.1.1	Image without alt text (cannot detect whether alt text provides an equivalent experience)
Color contrast	1.4.3	Poor contrast ratios in text against simple backgrounds (excluding images of text)
Missing labels	1.3.1	Form fields unlabeled
Empty links	2.4.4	“Click here” links
Missing title	2.4.2	Page without title

 

Examples of issues that typically require manual evaluation

Issue type	WCAG criterion	Example
Alt text quality	1.1.1	Alt text does not provide an equivalent to the non-text content in context.
Reading order	1.3.2	The order of information in a web page, PDF, or PPT is not correctly sequenced for users of assistive technology like screen readers.
Focus order	2.4.3	Focus moves in the wrong order on a web page, making it difficult for keyboard-only users to navigate content.
Error clarity	3.3.1	An error message for a form does not clearly explain how a user can correctly complete the form.
Navigation consistency	2.4.5	Navigation menus are structured differently across different pages of a website.

Types of automated accessibility testing tools

Accessibility testing tools fall into several categories that correspond to different test frameworks. These essential tools include browser extensions, developer tools (including SDKs and CI/CD integrations), and monitoring dashboards.

• Browser extensions: Free web accessibility browser extensions, including the WAVE tool by WebAIM and Google Lighthouse, are an easy way to get a quick snapshot of a web page’s accessibility. While free tools provide a quick entry point into automated testing, paid tools can provide deeper insight on accessibility issues and support a broader range of use cases. For example, the Level Access Browser Extension enables teams to scan code in any environment (local, pre-production, live, or secure environments) and provides key context to support issue prioritization and remediation.
• Developer tools: Tools for developers, like software development kits (SDKs) and CI/CD integrations, help teams proactively embed accessibility checks into the build process. For example, our Level CI tool allows developers to test code and receive remediation guidance directly in their pull requests. It also supports the setup of custom accessibility quality gates that prevent inaccessible code from being merged into the branch.
• Monitoring dashboards: Monitoring tools provide continuous insight on digital accessibility progress by running recurring scans. These tools are particularly helpful for tracking accessibility across large and frequently changing websites.

How to implement automated accessibility testing

Automated accessibility testing is most effective when it is embedded across your development lifecycle, not treated as a one-time activity. The steps below outline a practical, scalable approach to building continuous accessibility coverage.

• Start with a free scan (optional): If you’re new to accessibility, consider starting with a free automated scan to gauge your accessibility status.
• Set up monitoring for web content: For a more reliable web accessibility benchmark, implement monitoring across your site. Remember, the results of your first scan are just your starting point: your conformance will improve as you start addressing accessibility violations.
• Supplement scanning with manual audits: Build on automation by engaging accessibility experts to evaluate important web pages, user flows, and components using testing libraries for comprehensive insight.
• Implement developer tools: Incorporate accessibility testing into the software development life cycle (SDLC) to prevent new issues from emerging. Equip teams with SDKs and / or CI/CD integrations with accessibility features that automatically catch errors before code is merged, as well as in QA.
• Continue to test and track progress: Continue to test at appropriate intervals, and track overall accessibility progress using an accessibility platform. The right accessibility testing cadence may depend on how frequently you update your digital experience; however, a standard best practice is to continually run automated checks during development (in pull requests, pre-merge, and in QA), run multiple tests throughout the year (preferably monthly), and obtain manual audits at least manually for key pages and user flows.

Accessibility testing frequency guide

Test type	Frequency
Developer tools	Continuous
Full site scans	At least once a month
Manual audits	At least annually (for key pages and user flows)

 

Getting started: Your automated accessibility testing roadmap

Automated accessibility testing is a powerful way to identify accessibility issues quickly, improve conformance to WCAG guidelines, and support inclusive digital experiences. By combining automated checks with manual evaluation, organizations can ensure that accessibility validation goes beyond testing accessibility using surface-level rules, and experiences truly meet the needs of users with disabilities.

Wondering whether your testing methods are catching all accessibility problems? Our team can help you evaluate your current testing tools, identify gaps where human judgment is required, and design a roadmap for accessibility improvements. Learn more about our auditing and testing solutions, or contact our team to get started providing seamless journeys for every user.

Frequently asked questions

What is automated accessibility testing?

Automated accessibility testing uses software to scan web pages for accessibility issues. These tools check for common issues like missing alt text, poor color contrast, and keyboard navigation problems. They can scan hundreds of pages in minutes, which makes them essential for large sites.

What can automated tools detect vs. what needs manual testing?

Accessibility automation can reliably catch common WCAG violations, like missing alt text, empty links, improper form labels, and low color contrast ratios. They struggle with contextual accessibility issues like whether alt text is meaningful, if reading order makes sense, or whether custom widgets work with screen readers. Think of it this way: automation handles the “what” while human testers judge the “whether it works” based on existing accessibility knowledge.

Is automated testing enough for WCAG conformance?

No. Automated accessibility testing cannot detect all issues, which is why manual evaluation is essential for complete insight. Tools can flag that an image has alt text, but only a person can judge if that text actually describes the image well. Many online tools are also prone to false positives, which could result in valuable resources being wasted on nonexistent issues. Use automation to catch obvious accessibility issues fast, then follow up with manual checks for contextual defects and to validate functionality for users of assistive technology, including screen reader users.

What accessibility issues do automated tools miss?

Automated tools miss anything requiring human logic. This includes whether focus order is logical, if content makes sense without visuals, whether interactive elements behave correctly, and if language is clear. They also miss accessibility issues in dynamic content that loads after the initial scan unless you configure them to interact with the page. Finally, they cannot check if the content supports assistive technologies, such as screen readers. Human evaluation brings essential accessibility knowledge and judgment.

How do I prioritize which issues to fix first?

Start with critical accessibility violations that block users entirely: keyboard traps, missing form labels, and images without alt text. Then address moderate issues affecting usability: the lack of sufficient contrast, missing headings, and unclear link text. Save low-severity issues for later unless you’re pursuing strict compliance certification.

What WCAG level should we aim for?

Most organizations target WCAG 2.1 Level AA. This is the legal standard in many regions and covers issues affecting the most users. Level A is the bare minimum. Level AAA touches on very specific success criteria, is rarely required, and often impractical to maintain across all content.

How often should we run accessibility tests?

Run tests on every pull request to catch new issues before they merge. Run full-site scans weekly or monthly to track overall health. Always retest after major releases or design changes. Catching problems early is cheaper than fixing them after launch.

How do I test my website for keyboard accessibility?

The most reliable way to test your website for keyboard accessibility is to engage a reputable third-party expert to conduct a manual audit. This audit should include evaluation by native users of keyboard-only navigation. However, you can perform a quick check by unplugging your mouse and trying to navigate your website using only your keyboard.