Imagine you’re scanning through an accessibility report when it flags a purely decorative image for missing alt text. You pause and double-check the code—aria-hidden= "true" is clearly set—yet the tool insists it’s an issue. In moments like these, you’re dealing with false positives.

When left unchecked, false positives can waste hours of development time, drain your budget, and leave real accessibility problems hidden beneath noise. For developers who regularly rely on automated accessibility testing, learning to recognize and reduce these inaccuracies is as essential as fixing actual accessibility barriers.

What a False Positive Really Is

Simply put, false positives occur when a testing tool incorrectly marks compliant content as inaccessible, even though it aligns perfectly with standards like WCAG. These mistaken alerts often create confusion and lead teams to fix things that aren’t broken—sometimes at the expense of overlooking real issues.

So, why do they happen? Usually, false positives stem from three common causes:

• Limited context: Automated tools understand code but not intent. Elements involving dynamic JavaScript or custom user settings can confuse them, triggering inaccurate alerts. For example, a modal loaded via JavaScript might be marked as inaccessible until it’s fully rendered, even if it meets all WCAG requirements when interactive.
• Overly cautious rules: Some tools are intentionally strict, flagging anything remotely questionable to avoid missing genuine issues. While well-intentioned, this can lead to excessive alerts. Developers end up treating these tools like overprotective smoke alarms—loud, constant, and sometimes hard to trust.
• Varied coding practices: Custom components or unconventional markup patterns, common in modern front-end workflows, often mislead algorithms expecting textbook HTML. Accessibility implemented through ARIA roles or JavaScript event handlers may trip up tools that expect static HTML structures.

Most developers have encountered these scenarios in practice: decorative icons labeled as “critical issues,” contrast alerts ignoring user-selected dark modes, or dynamic form elements incorrectly flagged for missing labels. Each instance represents the broader problem—tools missing the bigger picture.

The Hidden Costs of False Positives

When false positives become part of your day-to-day workflow, the cost isn’t just inconvenience—it’s real impact on time, trust, and outcomes.

Time and Budget Drain

Chasing down false positives can quickly become a costly distraction. Imagine your team spends hours rewriting alt text for images that never needed it. Those same resources could have resolved genuine issues or shipped new features, improving your product instead of spinning its wheels. For larger teams or enterprise projects, these hours quickly compound into days—adding up to measurable delays in delivery and inflated budgets.

This resource drain can be particularly painful during audits or compliance deadlines when teams are working under pressure. Every misfire takes attention away from what truly matters: building inclusive digital experiences for real users.

Erosion of Trust in Tools

Repeated inaccurate alerts erode confidence in accessibility tools. Developers may grow skeptical, dismissing genuine issues as “probably another false positive.” This skepticism can cause real accessibility problems to slip through unnoticed, undermining the very purpose of using these tools.

Once the trust is gone, so is the motivation to use these tools proactively. Instead of integrating accessibility checks early and often, teams may push them off to the final stages—or abandon them altogether. That’s a slippery slope that compromises both compliance and user experience.

Legal and Reputational Risks

Perhaps most serious of all, excessive false positives can mask true accessibility problems. If your team assumes a website is compliant based on misleading tool reports, users could face unexpected barriers. That scenario leaves your organization vulnerable to lawsuits, fines, and damage to brand reputation.

It’s a dangerous combination: a dashboard showing 100% compliance while screen reader users struggle to navigate key interactions. In the worst-case scenario, this could lead to legal action under ADA, Section 508, or similar laws depending on your location or industry.

Practical Steps to Minimize False Positives

It’s not about choosing between automation and accuracy—it’s about striking a balance. Here are a few strategies that can help:

Choose Tools Carefully

Accuracy is crucial. Opt for tools known to minimize false positives—look at reviews, user communities, and real-world feedback. Tools that offer detailed explanations for each issue help developers evaluate the context instead of blindly applying changes. Bonus points for tools that integrate smoothly into your CI/CD pipeline or Git workflows, allowing developers to spot and triage issues earlier in the process.

Combine Automated Testing with Manual Checks

Automation is valuable, but humans bring the necessary context. Regular manual reviews, particularly with real assistive technologies like screen readers or keyboard-only navigation, confirm whether flagged issues are real or simply more false positives. This human element provides critical insights into actual user experiences that no machine can replicate on its own.

Pairing automated scans with periodic expert reviews ensures you don’t end up trusting the scanner more than the people you’re building for.

Educate and Empower Your Team

Providing training ensures everyone knows what a genuine accessibility issue looks like. Regular team briefings, quick reference guides, or lunch-and-learn sessions can equip developers and QA specialists to confidently distinguish true issues from false positives during daily workflows.

It also helps to document commonly misflagged elements in your internal dev wiki or design system docs. That way, developers don’t waste time rediscovering the same conclusions again and again.

Shift Accessibility Testing Left

Accessibility testing should be a routine practice, integrated into every development phase—right alongside linting, unit testing, and code reviews. Early checks catch issues and limit the spread of false positives throughout your codebase.

This shift-left approach reduces last-minute panic before launches and promotes a culture where accessibility is part of the conversation from the start. Teams that embed these habits often find they’re able to respond to flagged issues faster and with greater confidence.

Engage Accessibility Specialists

Sometimes, complex implementations or large-scale projects need specialized insight. Accessibility experts can fine-tune automated testing parameters, spot challenging edge cases, and provide tailored recommendations. Their guidance helps reduce false positives and sets your project on a sustainable path forward.

Even a short-term partnership or audit can clarify which alerts deserve attention and which are tool-generated noise. Think of it like calling in an electrician to check wiring behind the walls—some things are better seen with trained eyes.

A True Positive Path Forward

False positives in accessibility testing aren’t just minor annoyances—they cost valuable resources, erode trust, and potentially expose your site to compliance risks. Left unchecked, they can derail good intentions and cause more confusion than clarity. But with the right balance of tools, process, and people, they don’t have to.

Start by picking better tools, pairing them with manual validation, and investing in your team’s knowledge. Make accessibility part of your workflow—not just a checkbox at the end. And when needed, bring in expert support to cut through the noise.

Want to take your accessibility efforts to the next level? Schedule an ADA briefing with 216digital. Our team will help you build a sustainable, practical strategy for achieving real-world accessibility and staying ahead of compliance requirements.