Accessibility Tools

In today’s digital era, inclusivity has become a vital aspect of web and mobile app development. With an ever-increasing global user base, it is crucial to ensure that digital platforms cater to the needs of individuals with diverse abilities, and whilst iImplementing accessibility features is the first step, verifying their effectiveness is equally important.

This article delves into the world of website and mobile app accessibility testing tools, offering valuable insights and comparisons to help you choose the most suitable options for your projects. We will explore a variety of tools, covering both automated and manual testing, as well explain how Filter tests our client sites for accessibility during design and build.

What is Accessibility?

Accessibility in the context of websites and mobile apps refers to the design and development of digital platforms that cater to the needs of individuals with diverse abilities, including those with visual, auditory, cognitive, or physical disabilities.

The core principle of accessibility is to ensure that no user is excluded or disadvantaged while interacting with digital content, regardless of their abilities or the devices they use. An accessible website or mobile app encompasses features such as easy navigation, perceivable content, and compatibility with assistive technologies, fostering a more inclusive and user-friendly experience for all.

Embracing accessibility not only helps organisations comply with legal regulations, such as the Americans with Disabilities Act (ADA) and the Web Content Accessibility Guidelines (WCAG), but also brings broader benefits to both users and businesses. A truly accessible platform attracts a wider audience, improves user satisfaction, and bolsters brand reputation.

For mobile apps, in particular, prioritising accessibility can lead to more downloads and higher user retention rates. As we strive for a more inclusive digital landscape, understanding and implementing accessibility in web and mobile app development is paramount for creating platforms that empower and accommodate everyone.

“Failure to comply with accessibility regulations can result in lawsuits, financial penalties, and damage to an organisation’s reputation.”

Accessibility guidelines and regulations

In the United Kingdom, the primary accessibility regulations for websites and mobile apps stem from the Equality Act 2010 and the Public Sector Bodies (Websites and Mobile Applications) (No. 2) Accessibility Regulations 2018.

The Equality Act mandates that organisations and service providers must ensure equal access to their digital platforms, making reasonable adjustments to prevent discrimination against individuals with disabilities. The Public Sector Bodies Regulations require public sector organisations to make their websites and mobile apps accessible in line with the Web Content Accessibility Guidelines (WCAG) 2.1 Level AA standards.

In the United States, website and mobile app accessibility is governed by the Americans with Disabilities Act (ADA) and Section 508 of the Rehabilitation Act. The ADA broadly covers accessibility requirements for both public and private organisations, requiring them to provide equal access to their digital content for individuals with disabilities.

Section 508 specifically targets federal agencies and organisations receiving federal funding, mandating that their electronic and information technology, including websites and mobile apps, must be accessible to individuals with disabilities, adhering to the WCAG 2.0 Level AA standards.

Businesses in both the UK and the US must follow these accessibility guidelines and regulations not only to comply with the law but also to demonstrate corporate social responsibility, reach a wider audience, and enhance user satisfaction.

Failure to comply with these regulations can result in lawsuits, financial penalties, and damage to an organisation’s reputation. By embracing accessibility and striving for digital inclusion, businesses can ensure that their platforms cater to a diverse user base, promote equality, and contribute to a more inclusive digital landscape.

Common Accessibility Problems

One common problem encountered while testing accessibility on websites and mobile apps is insufficient contrast between text and background colours. This issue can make it difficult for users with low vision or colour vision deficiencies to read and interpret content.

Additionally, missing or improper alternative text for images, known as alt text, poses challenges for screen reader users who rely on these textual descriptions to understand the visual content.

Other typical issues include the lack of keyboard navigation support, which affects users who cannot use a mouse, and the absence of proper labels and landmarks for form elements and page sections, making navigation harder for those relying on assistive technologies.

In mobile apps, common accessibility issues often involve touch targets that are too small or too close together, leading to challenges for users with motor impairments or limited dexterity.

Mobile apps may also lack support for screen reader gestures, making it difficult for visually impaired users to access all app features. Additionally, handling dynamic content, such as real-time updates and pop-up messages, can pose challenges if not implemented with accessibility in mind.

Failure to provide proper focus order, suitable text resizing options, and support for both portrait and landscape orientations further exacerbates the inaccessibility of mobile apps for users with disabilities.

Accessibility Guide

The Marketers Guide to Web Accessibility

Download our FREE guide to web accessibility on web platforms to find out more

Automated Accessibility Testing tools

Not all testing tools work the same way, or provide the information you need, and they all offer their own point of difference.

In this section, we will explore various automated tools, highlighting their key features and discussing their respective advantages and disadvantages. This information will help you make an informed decision when choosing the most suitable testing tool for your project.


WAVE (Web Accessibility Evaluation Tool)
Pros: WAVE is free to use, while being easy to install as a browser extension or via the web interface. It provides visual feedback of accessibility issues directly on the web page, as well as offering detailed explanations and suggestions for fixing detected issues.

Cons: This tool only analyses one page at a time, making large-scale testing time-consuming. It could also produce false positives or negatives.

Ideal for: Quick and easy accessibility testing during development, for smaller websites or individual pages.


Pros: Lighthouse is open-source and available as a browser extension or integrated into Chrome DevTools. This tool provides comprehensive audits, including accessibility, performance, SEO and uses a scoring system and detailed guidance for improving accessibility.

Cons: Lighthouse is limited to testing individual pages rather than full websites and may not detect all possible accessibility issues.

Ideal for: Web developers looking for an integrated solution for auditing multiple aspects of a website, including accessibility.


Pros: Axe is fully open-source and available as a browser extension, CLI, or integrated into testing frameworks. It is highly accurate with minimal false positives and offers a comprehensive API with customizable rules.

Cons: This tool only analyses individual pages, not entire websites and also requires some technical knowledge to fully utilise

Ideal for: Web developers and QA professionals seeking to integrate accessibility testing into their development process and testing frameworks.
Pros: has a robust API for integrating into development and testing environments and is capable of testing entire websites. It can provide detailed documentation and support for fixing issues.

Cons: A subscription is required for full features and higher volume testing and there is no browser extension available.

Ideal for: Large-scale web projects or organisations looking to integrate accessibility testing into their development and testing workflows.


Pros: SiteImprove offers a comprehensive platform for managing web accessibility, performance, and SEO. It is capable of testing entire websites and provides detailed reports and prioritised issue lists.

Cons: SiteImprove requires a subscription, which can be expensive for small businesses or individual developers. Currently, there is no free or trial version available.

Ideal for: Medium to large organisations seeking a comprehensive solution for web accessibility and other aspects of digital presence management.

“Using automated tools should be complemented by manual testing and user feedback.”

Manual Testing Tools

Automated accessibility testing tools, while helpful for identifying and fixing issues, may not catch all accessibility issues, and relying solely on them can lead to an incomplete understanding of the user experience for individuals with disabilities. Using automated tools should be complemented by manual testing and user feedback, and below are some of the ways in which you can do this.


NVDA (NonVisual Desktop Access) Screen Reader

Pros: It offers a free and open-source screen reader for Windows, which is regularly updated and maintained, and also provides a realistic experience of how visually impaired users navigate websites.

Cons: It is limited to the Windows platform, and may require some time to learn and become proficient with.

Ideal for: Web developers and testers using Windows who want to evaluate their websites from the perspective of screen reader users.


JAWS (Job Access With Speech) Screen Reader

Pros: JAWS is widely used and is recognized as the industry standard for screen readers. It’s highly customizable and feature-rich while offering compatibility with a wide range of web browsers and assistive technologies.


This tool can be expensive, which makes it less accessible for small businesses or individual developers. It also has a steeper learning curve compared to some other screen readers.

Ideal for: Large organisations and professionals who require a powerful and widely-used screen reader for accessibility testing.



Pros: VoiceOver has an integrated screen reader for macOS, iOS, and iPadOS devices. This tool is easy to enable and navigate using built-in keyboard commands and provides a consistent user experience across Apple devices.

Cons: This solution is limited to Apple devices and may not cover all possible scenarios encountered by users of different screen readers.

Ideal for: Web developers and testers using Apple devices who want to test their websites and mobile apps for accessibility on the Apple ecosystem.

What does Filter use for accessibility testing?

Automated accessibility testing tools, while helpful for identifying and fixing issues, may not catch all accessibility issues, and relying solely on

We don’t just rely upon our ability to look at a site and tick a box to meet the guidelines.

In the design phase we use tools such as Stark, which plugs directly into Figma, and ensures that the the colours we are employing for the design do not cause any contrast issues using resources like ​​this.

During development, we evaluate the work we are doing in an ongoing manner using the WAVE Evolution Chrome plug-in.

Finally, we put the sites that we develop to the test using tools such as SortSite, which runs a full scan of every single page on a site and highlights any potential issues where the guidelines are not being met.

This process is completed during the initial QA phase, when we have loaded in draft content for users to test with. Once the full content load is complete on UAT, we then perform a second scan to check if anything has changed as the content has been added.


Filter also partners with agencies that have specialist knowledge of accessibility and usability issues, and can provide further support by testing to an enhanced level.

Web Usability serves as our partner for clients seeking a thorough accessibility performance evaluation and rectification procedures. Our familiarity with working alongside Web Usability enables us to cooperate seamlessly, ensuring the delivery of an ideal solution.

Able Docs collaborates with us to support clients who have numerous PDFs and document files requiring proper tagging and formatting for accessibility. As a worldwide frontrunner in the realm of accessible documents, Able Docs possesses an automated scanning platform that offers an in-depth analysis of file structures.

them can lead to an incomplete understanding of the user experience for individuals with disabilities. Using automated tools should be complemented by manual testing and user feedback, and below are some of the ways in which you can do this.

Web Usability

User experience specialists

Our partner for clients that would like a comprehensive accessibility performance check and remediation process. We are used to working with Web Usability, which means that we are able to work closely together for an optimal solution. 


Digital accessibility provider

Our partner for clients with large numbers of PDF and document files that need correctly tagging and formatting for accessibility. They are a global leader in the area of accessible documents, and have their own automated scanning platform that provides a deep understanding of the structure of files.

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Frequently Asked Questions

Automated accessibility testing tools use algorithms to scan web pages or mobile apps for accessibility issues, while manual testing tools typically involve human interaction with the site or app, such as using a screen reader or navigating with a keyboard.
No, automated tools can detect many common issues, but they may not catch all potential problems. Combining automated testing with manual testing and user feedback ensures a more comprehensive assessment of accessibility.
Yes, there are several free tools, such as WAVE, Lighthouse, and axe, which offer basic accessibility testing functionality.
Some widely-used screen readers include NVDA (NonVisual Desktop Access) for Windows, JAWS (Job Access With Speech) for Windows, and VoiceOver for macOS, iOS, and iPadOS devices.
Consider factors such as the size and complexity of your project, your budget, the platforms and devices you need to support, and the level of integration you require with your existing development and testing processes.
While many web accessibility testing tools can be used for mobile apps, there are also platform-specific testing tools like Google’s Accessibility Scanner for Android and Apple’s Accessibility Inspector for iOS.
Yes, many tools such as axe and offer APIs or integration options that allow you to incorporate accessibility testing into your development and testing workflows.
Accessibility testing should be conducted regularly, ideally as part of your development and testing processes. This helps ensure that any new features or updates do not introduce new accessibility issues.
Yes, organisations like the International Association of Accessibility Professionals (IAAP) offer certification programs and resources for learning about accessibility testing and best practices. Additionally, many online courses, workshops, and tutorials are available to help build your accessibility testing skills.