Accessibility Testing in Design Systems: Best Practices
Having a well-functioning, aesthetically pleasing website is not enough. If you are wondering why, the answer is simple. It has to pass the critical aspect of accessibility testing in the design system.
About 1.3 billion people in the world, accounting for 16% of the global population, live with significant disability currently. So yes, it is of supreme importance to ensure that your products are accessible to people with disabilities.
In this blog, we will unravel how you can make your products absolutely accessible by hitting at the very root… your design system.
What is a Design System?
A design system is a holistic set of standards, building blocks, and guidelines that help keep the overall appearance and style of products consistent. Developers and designers use these rules to design products that offer a unified visual language and user experience across products and platforms.
Importance of Accessibility Testing in Design System
Accessibility testing is the process of examining web and mobile applications to check whether these can be used smoothly by persons with disabilities, irrespective of the nature of their disabilities being auditory, motor, visual, or cognitive.
Only 3% of the internet is currently accessible. This underscores the need for accessibility testing in the design system to create an enriching, inclusive digital experience for all.
Developers and testers conduct rigorous accessibility testing of products against standard frameworks such as the WCAG (Web Content Accessibility Guidelines).
98% of websites don’t comply with WCAG 2.1. Regulations such as the Americans with Disabilities Act (ADA), Section 508 in the U.S., and similar global standards mandate that digital products must be accessible to people with disabilities.
Non-compliance can lead to lawsuits, fines, and reputational damage. The end of 2024 saw a 7% increase in ADA lawsuits against organizations, with a total of 8,800 ADA Title III complaints filed.
No wonder why accessibility testing is essential in opening up your product to a much broader audience. It future-proofs digital experiences while strengthening brand trust.
Best Practices for Accessibility Testing in Design Systems
Embedding accessibility into design stages results in a 30x cost reduction if compared with making accessibility fixes in the post-production phase. Honestly, accessibility testing isn’t a one-time checkbox either. It’s a continuous habit that needs to be built into your design system.
Let’s look at the five best practices that you can follow:
- Define Accessibility Standards Early
First, start with clear accessibility goals. It’s not a good idea to wait until the product is ready to test.
From the very first design sprint, define which guidelines you’ll follow, like WCAG (Web Content Accessibility Guidelines), ADA (Americans with Disabilities Act), or Section 508. These standards give your team a shared language.
If your organization offers or uses design system services, make sure these services embed accessibility tokens, color contrast rules, and alt-text usage right into the design system from day one.
- Component-level Testing
Your design system is made of reusable parts such as buttons, forms, modals, navigation menus, and color palettes. So, make sure to test each one.
Just because a button looks fine, don’t assume that it will work for everyone. Check tab order, focus states, and label associations.
When each component is accessible on its own, your entire product inherits those good habits. This is especially powerful when scaling with design system services, because a fix in one place benefits every product using the system.
- Automated Testing Tools
You can use tools like Axe, Lighthouse, or Storybook accessibility add-ons, as these can quickly scan for common accessibility issues such as missing alt text or poor color contrast.
Run them during development, in your CI pipeline, or even inside your browser. But don’t rely on them alone.
Automation only catches about 30-40 % of issues. It’s fast and helpful, but not enough. Following it up with human review is a must.
- Manual & Assistive Technology Testing
This is where the human touch matters, you see. Try using your product with only a keyboard, and no mouse.
Can you reach every link and button? Does the focus indicator show up clearly? Then test with screen readers like NVDA, JAWS, or VoiceOver.
Listen to how your interface “sounds.” Is it logical? Is it overwhelming? These steps reveal problems automation can’t. Accessibility is about people, after all. So, it is essential to put yourself in their shoes.
- Inclusive Design Reviews & Continuous Audits
Make inclusive design reviews a regular part of your design process. Invite peers to review new components. Better yet, involve users with disabilities in usability testing sessions, if possible. Their feedback is paramount.
Also, schedule accessibility audits at regular intervals, especially when your design system grows or updates.
A design system that evolves needs accessibility to evolve with it. And, guess what? Continuous auditing ensures you don’t slip back into bad habits.
How Design System Services Support Accessibility
Not every team has the in-house expertise to make accessibility a seamless part of their design system. That’s exactly where design system services come in.
Specialized agencies help organizations build scalable frameworks where accessibility is inherently woven into every component. From streamlined testing to expert audits and compliance consulting, these services ensure your digital products meet global standards while staying consistent with your brand.
Every dollar invested in web accessibility brings back $100, giving an ROI of 99%. Therefore, collaborating with the right partner is vital as it helps future-proof your system as accessibility keeps evolving with changing guidelines and user needs.
Agencies like Onething.design stand out in this space, combining deep design system expertise with accessibility-first thinking. By collaborating with such teams, enterprises can confidently scale products that are both elegant and inclusive.
Final Words
71% of users will immediately leave a website within 10 seconds if they encounter an inaccessible design. That’s a huge loss of trust and opportunity.
Accessibility testing in design systems is all about keeping people engaged and included. When you weave accessibility into your design system, you’re building experiences that scale without leaving anyone behind.
The most awesome part, you ask? With the right design system services, you don’t have to do it alone. So, go ahead… build systems that scale, but also systems that everyone can truly use and enjoy.