Website Accessibility Checkers - Use Cases, Pros and Cons

Ensuring your website is inclusive and accessible is not just good practice—it's often a legal necessity. Website accessibility checkers (also known as ADA compliance tools or automated WCAG testing tools) have emerged as a popular way to evaluate if a site meets accessibility standards quickly. 

These tools scan web pages for issues that might hinder users with disabilities, such as missing alt text or poor color contrast. But how should developers, business owners, and accessibility specialists use these checkers effectively? In this article, we’ll explore the common use cases for website accessibility checkers, their key pros and cons, and how to integrate them into a comprehensive accessibility strategy.

What are website accessibility checkers?

Website accessibility checkers are automated testing tools that review your site’s content and code to identify potential accessibility problems. They typically measure your site against standards like the Web Content Accessibility Guidelines (WCAG) and regulations such as the ADA (Americans with Disabilities Act). With a checker, you can get a report in seconds highlighting issues like unlabeled form fields, missing image descriptions, or insufficient text contrast. For example, a tool might report the number of errors, alerts, and features on a page as shown below

These tools come in various forms—browser extensions, web-based scanners, and CI/CD integrations—but they all serve the same purpose: to automate WCAG testing and give you a quick snapshot of your site’s accessibility. Importantly, while they are sometimes called ADA compliance tools, no automated checker can guarantee full compliance on its own. They are best used as an early warning system to catch common issues, which you can then follow up with a manual review.

Use cases of website accessibility checkers

Automated accessibility checkers can be applied in many scenarios throughout a website’s lifecycle. Below are some key use cases where these tools prove especially useful.

Pre-launch accessibility audits

One of the most common use cases is scanning a website or web application before it goes live. During development or right before launch, developers can run an accessibility checker to catch and fix obvious issues early. For example, if you’re building a new e-commerce site, running a checker on key pages (home page, product pages, checkout) will highlight missing alt attributes on images or buttons without labels. This pre-launch audit helps ensure that major barriers are addressed upfront so you release a more WCAG-compliant product from day one.

In practice, teams often integrate accessibility checks into their QA process. A developer might use a tool like Axe or Lighthouse in their browser to test new components for accessibility. By catching errors (such as improper heading structure or non-accessible form controls) during development, you save time and avoid costly rework later. Automated accessibility testing at this stage acts as a safety net, preventing easily detectable issues from ever reaching end users.

Note! There is a huge emphasis on “easily detectable” issues. Automated checker audits can provide false positives and miss essential problems that could even allow others to sue you. 

Ongoing compliance monitoring for live sites

After your site is live, accessibility is not a one-time effort. Websites undergo frequent updates – new content gets added, designs change, and features roll out. An accessibility checker can be used for ongoing monitoring to ensure these changes don’t introduce new accessibility problems. Many businesses schedule periodic scans (e.g., weekly or monthly) of their websites using automated tools. This continuous monitoring is especially important for content-heavy sites or those with multiple contributors, where an innocuous change (like an editor adding an image without alt text) could inadvertently reduce accessibility.

For instance, a large news website might use an accessibility checker to scan its top articles every day for issues. If the tool flags something – say a low-contrast text in a new article layout – the web team can promptly fix it. By regularly monitoring in this way, organizations maintain WCAG compliance over time and catch regressions early. Some advanced checkers even support scheduling and dashboards, making it easier for teams to track their compliance status release after release.

Ensuring legal compliance and ADA conformance

Another critical use case for accessibility checkers is assessing legal compliance. In many regions, maintaining an accessible website is required by law. For example, in the U.S., websites of businesses and public entities may need to comply with the ADA and Section 508, while other countries have their regulations. Automated checkers can quickly evaluate if your site meets key criteria of these laws by checking against WCAG standards (which form the basis of most accessibility legislation)​. Using a checker is a fast way to gauge whether you're on the right track with ADA compliance and identify problem areas that could put your organization at risk.

Companies facing industry regulations or those who have received complaints will often run an accessibility scan as a first step. The report from the tool serves as a reference for which issues to address to comply with the law. For example, a bank’s website might be scanned to ensure it has no critical ADA violations before a regulatory review. While a manual audit is ultimately needed for full verification, an automated checker is a cost-effective preliminary audit. It demonstrates proactive effort – useful if you need to show stakeholders or legal advisors that you are taking compliance seriously. (Keep in mind that if an automated report shows many errors, it's a clear sign you need to improve accessibility to avoid potential lawsuits, which have been rising in recent years​).

Integrating accessibility into development and CI/CD pipelines

Modern development practices encourage catching issues as early as possible, and accessibility is no exception. Many teams use accessibility checkers integrated into their development workflow or CI/CD pipelines. In this use case, every time developers push new code or content, an automated test runs the checker on the updated pages. If the build introduces an accessibility error (for example, a new UI component without proper ARIA labels), the pipeline can flag it or even fail the build. This integration treats accessibility bugs just like any other regression, ensuring they are caught and fixed during development rather than after deployment.

For example, a software team might include an accessibility testing step using axe-core or Google Lighthouse in their continuous integration setup. Each pull request could trigger an accessibility scan of the affected pages. If the scanner reports violations (like a form missing a label or a color contrast issue), the team is notified immediately. This continuous automated accessibility testing helps maintain high standards over time. It’s especially useful for large applications where manually re-testing everything is impractical. By baking accessibility checks into your pipeline, you create a culture where accessibility is checked on every code change, just as unit tests or security scans would be.

Quick checks for content publishers and designers

Beyond developers, accessibility checkers are also handy for content editors and designers as a final review tool. A content publisher can run a quick check on a blog post or landing page they just composed to ensure things like headings are structured and link texts are descriptive. Designers can use color contrast analyzer tools (a form of accessibility checker) during the design phase to test if their color choices meet color contrast requirements. In this use case, the checker acts as a teaching and guiding tool. It helps team members who might not be accessibility experts catch common mistakes in their work.

For instance, a marketing team creating a new campaign page might use a checker to verify that all interactive elements (buttons, forms) are accessible via keyboard and that images have alt tags. If the tool flags issues, the team can adjust the content or design before publishing. This not only improves the immediate project but also educates the team—over time, content creators learn from these tools what to do (or avoid) to make content accessible. In this way, accessibility checkers support a broader goal of building organizational awareness around accessibility best practices.

Pros of using website accessibility checkers

Automated accessibility checkers offer several advantages that make them valuable as part of your toolkit. Below is a breakdown of the major pros or benefits of using website accessibility checker tools.

1. Quick and efficient auditing of web pages

One of the biggest advantages of accessibility checkers is their speed and efficiency. These tools can scan multiple pages in a matter of seconds or minutes, flagging issues that might take a human tester hours to find. For example, an automated checker can crawl through dozens of URLs on your site overnight and output a report by morning – something manual testing alone cannot match in speed. This efficiency is invaluable, especially for large websites. If you have hundreds or thousands of pages, an automated tool is practically the only feasible way to identify obvious accessibility problems at scale.

The efficiency extends to development as well: a quick run of a browser-based checker gives immediate feedback to a developer working on a single page. Instead of manually tabbing through every element or inspecting code line-by-line, the tool highlights known issue patterns in one go. This allows teams to save time and resources, focusing their manual effort on fixing issues rather than hunting for them. In short, accessibility checkers dramatically accelerate the initial evaluation process, making it possible to maintain accessibility even under tight deadlines or with limited staff.

2. Cost-effective and easily accessible tools

Most web accessibility checkers are either free or relatively low-cost, which makes them very accessible to organizations of all sizes. Many popular tools (like WAVE, Axe, and Google Lighthouse) cost nothing to use. This low barrier to entry means even small businesses or individual developers can start testing for accessibility without needing a budget or special equipment. By using these free ADA compliance tools, companies can catch issues early and avoid the potentially high costs of retrofitting a site after a lawsuit or complaint.

Even for paid enterprise-level checkers, the return on investment can be high. The automated nature of these tools reduces the hours QA teams might spend on repetitive checks. In effect, they lower the cost of compliance by handling routine audit tasks. Moreover, because checkers are software-based, they’re available 24/7. You don’t have to schedule a specialist every time you want to test a page – just run the tool. This on-demand availability is a cost and time-saver for fast-moving development cycles. Overall, accessibility checkers provide a budget-friendly way to kickstart your compliance efforts, complementing more thorough manual audits.

3. Immediate feedback and guidance on issues

Accessibility checkers don’t just spit out error counts; they usually provide details on each issue and often suggest ways to fix them. This immediate feedback is a huge pro, especially for developers who may not be well-versed in accessibility standards. When you run a checker, you get a list of specific issues (e.g., “Image X is missing alternative text” or “Button Y has low color contrast”) and, in many tools, an explanation of why it matters and how to fix it. This guidance accelerates the remediation process. Developers can learn on the fly about accessibility by reading the tool’s recommendations and adjusting their code accordingly.

For example, if a checker flags an <h1> used for a logo that should have been marked up differently, it will typically explain that headings should reflect page structure, not be used purely for styling. The developer now understands the rationale and can make the correct change (perhaps using CSS for style instead of a heading tag for the logo). In this way, checkers serve as a learning tool, educating your team about best practices while they fix issues. The instant feedback loop – find an issue, learn why it’s an issue, fix it – helps improve not just the current project but the developer’s knowledge for future projects. It’s like having an accessibility coach built into your testing process.

4. Enhanced compliance and risk mitigation

Using accessibility checkers regularly can significantly boost your compliance efforts and reduce legal risk. These tools systematically check for known WCAG criteria violations, which means they can help ensure you haven’t overlooked the “low-hanging fruit” of accessibility. By catching common issues (like form fields without labels or links that rely on color alone), checkers help you avoid obvious compliance failures. This is critical in an era of rising ADA lawsuits related to websites. An automated tool can act as an early warning system so that you can fix problems before they become legal liabilities.

While passing an automated scan doesn’t guarantee full ADA compliance, it certainly puts you in a better position. Think of it this way: if an automated checker finds 50 errors on your homepage and you address them, you’ve likely removed 50 instances where you were not conforming to WCAG success criteria. That’s 50 fewer issues a plaintiff or regulator could point out. Organizations that incorporate automated testing into their workflow demonstrate a proactive stance on accessibility, which can be beneficial if they ever need to prove due diligence. In summary, checkers are a fast track to improve compliance with standards and, as a result, they help mitigate the risk of lawsuits or fines by ensuring that many common accessibility barriers are eliminated.

5. Improved user experience (UX) and SEO benefits

Interestingly, the benefits of using accessibility checkers extend beyond just serving users with disabilities or avoiding lawsuits. Many fixes prompted by these tools will also improve the overall user experience for everyone. For example, ensuring proper heading structure not only helps screen reader users but also makes the page more digestible for all users (and search engines). Adding alt text to images not only makes them accessible to blind users but also gives Google information about the image, potentially boosting your SEO. Accessible websites often rank better in search results because they are typically faster, have clearer structures, and use best practices that search engines reward.

By systematically fixing issues that checkers identify, you may see side benefits like lower bounce rates (as content becomes easier to navigate), better mobile usability, and higher customer satisfaction. For instance, a contrast issue flagged by a tool, once fixed, means the text is now easier to read in sunlight on a mobile phone—benefiting all users, not just those with low vision. WCAG testing overlaps with good design and coding practices, so an accessible site tends to be a well-built site. From an SEO perspective, some accessibility improvements (like using proper tags and providing transcripts/captions for media) can increase your content’s visibility and ranking. Thus, investing time in automated accessibility checks and subsequent fixes can yield a double return: a more inclusive site and a more user-friendly, discoverable site.

Cons of using website accessibility checkers

While accessibility checkers are incredibly useful, it’s important to understand their limitations. Automated tools are not a silver bullet. Take a look at our overview of the main cons or drawbacks of relying on website accessibility checkers.

1. Limited coverage: They can’t catch everything

Perhaps the biggest drawback of automated checkers is that they only catch a portion of all accessibility issues. Studies and experts have noted that automated tools can reliably detect only about 20–30% of accessibility problems on a website​.

The reason is that many WCAG guidelines require human judgment to evaluate. For example, a tool can tell you if an image tag is missing alt text, but it cannot tell you if the alt text you provided is actually descriptive and useful. It might check if a form has some label, but it can’t judge if that label makes sense to a user. Issues like logical reading order, whether link texts make sense out of context, or whether the overall user flow is accessible, are beyond the scope of automation.

Because of this limited rule-based coverage, critical issues can be missed by checkers. An automated scan might give a site a “good” score while completely overlooking problems like a poorly structured navigation menu that confuses screen reader users, or an image slideshow that is difficult to operate via keyboard. Over-relying on the tool’s report could leave you with a false sense of security. Always remember that a clean automated scan does not equal a fully accessible website. Significant barriers might still exist that only a manual audit or real user testing will uncover. In short, checkers are just the starting point – human expertise is needed to catch the remaining 70–80% of issues that tools don’t flag.

2. False positives and the need for interpretation

Automated checkers are not perfect; sometimes they flag issues that aren’t actually problems or fail to contextually understand your content. These false positives can be confusing. For instance, a checker might mark a warning for a “missing form label” on a search icon that isn’t a form input at all. Or it might flag low contrast on a disabled button that users never need to interact with. These situations require a human to interpret whether the flagged item is truly an accessibility violation or if it’s an acceptable implementation. Without experience, a developer might waste time chasing down an issue the tool raised that turns out not to be a real problem, or conversely, might ignore a warning that was important.

The language of the reports can also be technical. Terms like “ARIA attribute misuse” or “semantic structure” might not be immediately clear to someone who isn’t familiar with accessibility jargon. It takes some learning to differentiate between critical errors, moderate issues, and mere suggestions in the output. In other words, the tools provide raw information, but making sense of it is up to you. This need for interpretation is a con because it means automated results are not as straightforward as, say, an automated spell checker. Misinterpreting the results could lead to either not fixing a genuine barrier or spending effort on something that isn’t actually hindering users.

3. Lack of human context and user experience insight

Accessibility is ultimately about human user experience – something automated checkers cannot inherently fully evaluate. A tool might tell you a page has all the required form labels and alt texts, but it can’t tell you if navigating that page is a frustrating experience for a person with a cognitive disability, or if the wording of a link is confusing. Many aspects of accessibility are contextual. For example, an automated checker could miss that a pop-up modal traps keyboard focus, making it impossible for a keyboard-only user to exit – because technically every element might have correct code, but the user flow is broken. Only a human tester would catch that kind of problem by actually trying to use the site with assistive technologies and various interaction methods.

Moreover, automated tools cannot judge content quality. Is the language simple enough to be understood by users with cognitive impairments? Is the layout predictable and helpful? These qualitative aspects are just as important for accessibility (they’re part of the higher-level WCAG guidelines) but a script can’t measure them. This is why you often hear that automated testing must be complemented with manual testing. The checker might be able to tell you the “letter of the law” (which technical rules pass or fail) but not the “spirit of the law” (whether a real person finds the site accessible and pleasant to use). Relying solely on checkers could leave significant user experience barriers unaddressed, which defeats the purpose of accessibility compliance in the first place.

4. Over-reliance can create a false sense of security

Because checkers are so quick and quantifiable, there’s a risk that teams might over-rely on them and believe their site is accessible just because the tool reports few errors. This is a cultural and process pitfall to watch out for. Accessibility compliance isn’t a checkbox you tick once with a tool – it’s an ongoing commitment. If an organization treats the automated checker report as the final verdict, they may become complacent. For example, a company might run a scan, see a 95% compliance score, and conclude “Great, we’re ADA compliant now!” without realizing that the 5% of issues not caught could be major blockers for users.

Over-reliance also appears when people use checkers as a substitute for involving real users with disabilities. No automated test can replicate the insights gained from actual user testing — such as a blind user navigating your site with a screen reader or a motor-impaired user trying to fill out a form using only a keyboard. If you skip those evaluations and only trust the tool, you might be in for a surprise later when users report problems that the tool didn’t flag. In summary, using checkers without a balanced strategy can lead to a false sense of security. Teams might declare victory prematurely, which is a con because it undermines the ultimate goal: making a site that is truly accessible in practice, not just on paper.

5. Requires ongoing updates and human oversight

Another drawback is that accessibility checkers (and the rules they use) need to be updated as standards evolve and web technologies change. WCAG itself updates over time (WCAG 2.2, 2.3, etc. introduce new success criteria), and new frontend techniques may pose new challenges. If your tool is outdated or not configured properly, it might not check for the latest best practices. For example, early versions of checkers might not have flagged issues related to newer HTML5 elements or ARIA patterns. Ensuring you use up-to-date tools and rule-sets is an extra responsibility. This also means you might need to periodically review which tool you’re using or update it to cover new criteria.

Moreover, someone on your team should own the process of reviewing the checker reports and verifying their findings. The human oversight aspect is crucial. If a tool flags 100 issues, humans need to prioritize them: which are real blockers vs. minor inconveniences? Which ones should be fixed first? The tool won’t do that thinking for you. This can be seen as a con because it’s not a plug-and-play solution—you must invest time to manage and act on the results continually. In other words, automated testing is not “set and forget.” It’s more like a smoke alarm: it will alert you, but you still need to actually put out the fire and keep maintaining the alarm system. For organizations looking for a one-time fix, this ongoing requirement might seem like a drawback, but it’s a necessary one to get real value from the tool.

Balancing automated and manual accessibility testing

Website accessibility checkers are powerful tools that provide quick insights and valuable assistance in the journey toward an accessible website. They shine in use cases like early development audits, large-scale scans, and ongoing monitoring, offering speed and efficiency that no manual method can match. The pros – from time savings and cost-effectiveness to immediate feedback and improved compliance – make them a must-have in any developer or tester’s toolkit for accessibility.

However, automated tools alone are not a complete solution. Their limitations (covering only ~30% of issues, requiring human interpretation, lacking context) mean that to truly achieve ADA/WCAG compliance and deliver a great experience to all users, you need to combine them with human expertise. The best approach is a hybrid strategy: use checkers to catch the easy-to-find issues and use manual testing (including expert reviews and real user testing) to handle the rest. For every error an automated checker fixes, there might be another issue that only a person can identify and resolve. By balancing both, you ensure that you’re not leaving significant gaps in your website’s accessibility.

In practice, start with an automated scan to get a baseline, then bring in accessibility specialists to delve deeper. If you’re unsure where to begin, you can even perform a quick automated scan using a free web accessibility checker (for example, TestDevLab offers a free quick check on their site) to see where your site stands.

From there, consider a comprehensive audit for full confidence. At TestDevLab, we offer accessibility testing services that include both automated checks and expert manual audits to help you meet all major guidelines and regulations. Our team can validate the issues found by tools, discover those hidden 70% of issues, and guide you on fixing them.

The bottom line

Use website accessibility checkers as a helpful ally to streamline your accessibility efforts, but don’t stop at their results. By addressing both the automated findings and the nuanced human-centric issues, you’ll move closer to a website that is truly inclusive, compliant, and user-friendly for everyone.

Want to see how well your web or mobile application complies with the accessibility standards described in the latest version of WCAG? Contact us to find out more about our accessibility testing services and how we can help you develop a more accessible product that is compliant with standards and regulations.