Web accessibility means websites work for everyone, including people with disabilities
Web accessibility is the practice of building websites and web applications so that people with disabilities can use them the same way anyone else can. A person who is blind should be able to navigate a website using a screen reader. A person with limited hand mobility should be able to use a keyboard instead of a mouse. Someone with low vision should be able to enlarge text without breaking the page layout. When a website is accessible, it works for people with hearing loss, color blindness, dyslexia, motor disabilities, and cognitive differences.
Accessibility is not a separate feature bolted onto a website. It is built into how the site is structured from the start — how headings are marked up, how images are described, how forms are labeled, how colors are chosen, how videos are captioned. A website that is accessible to people with disabilities is usually easier to use for everyone: better keyboard navigation helps people in a hurry, captions help people in noisy environments, clear language helps people learning English.
The web was designed to be accessible. The World Wide Web Consortium (W3C) publishes the Web Content Accessibility Guidelines (WCAG), which spell out the specific technical standards websites should meet. Many countries have laws requiring public websites and some private websites to meet these standards. In the United States, the Americans with Disabilities Act (ADA) applies to websites of businesses and government agencies. The European Union requires public sector websites to meet WCAG 2.1 Level AA.
Key Takeaways
- Accessible websites work with screen readers, keyboard-only navigation, and text enlargement tools that people with disabilities rely on.
- Accessibility is built into a website's code and structure, not added as an afterthought — it affects how headings, images, forms, and videos are created.
- Many countries legally require websites to be accessible, including government and business websites in the United States and public sector websites in Europe.
- Features that make websites accessible often help everyone — captions benefit people in loud places, keyboard navigation helps people without a mouse, and clear language helps non-native speakers.
How screen readers and assistive technology use accessible websites
A screen reader is software that reads the text on a screen aloud. A person who is blind or has severe low vision uses a screen reader to navigate websites, read documents, and use applications. For a screen reader to work, the website must be built in a way that the screen reader can understand — images need text descriptions, form fields need labels, buttons need to be marked as buttons, and the order of content needs to make sense when read aloud.
When a website is not accessible, a screen reader user encounters broken links, unlabeled buttons, images with no descriptions, and content in an order that makes no sense. They may not know what a button does, where a form field is, or what information an image contains. A person using a keyboard alone (because they cannot use a mouse due to a motor disability or injury) needs every interactive element to be reachable by pressing Tab, and needs to know which element is currently selected. A person with low vision needs to be able to enlarge text to 200 percent without the page breaking, and needs sufficient contrast between text and background so the words are readable.
Other assistive technologies include speech recognition software (which lets people control a computer by voice), magnification software, and specialized keyboards or switches. All of these depend on websites being built to web standards so the technology can interact with them reliably.
What makes a website inaccessible
The most common accessibility problems are images without descriptions, form fields without labels, and content that cannot be navigated by keyboard alone. A website that relies entirely on a mouse — where you have to click a button to reveal a menu, for example — locks out anyone using a keyboard or voice control. A website that uses color alone to convey information (like a red line meaning "error" with no text explanation) is unusable for people with color blindness.
Videos without captions are inaccessible to people who are deaf or hard of hearing, and also to people watching in a noisy environment or without sound. Websites with poor contrast — light gray text on a white background, for example — are hard to read for people with low vision and for anyone reading on a bright screen. Websites that use only images of text (instead of actual text) cannot be enlarged, cannot be read by screen readers, and cannot be searched.
Some accessibility problems are invisible to people without disabilities. A form field that looks fine visually might have no label attached to it in the code, so a screen reader user does not know what to type. A button might be marked as a link in the code, confusing screen reader users about what will happen when they set up it. A page might have no headings, so a screen reader user cannot jump between sections the way sighted users can scan the page visually.
The difference between accessibility and usability
Accessibility means a website works for people with disabilities. Usability means a website is straightforward for anyone to use — the layout is clear, the navigation makes sense, the language is plain, the buttons are straightforward to find. A website can be accessible but not usable (it works with a screen reader but the navigation is confusing), or usable but not accessible (it is straightforward to navigate visually but does not work with a keyboard). The best websites are both.
Accessibility is about removing barriers for people with disabilities. Usability is about making something work well for everyone. They overlap — a website with clear headings is more accessible to screen reader users and more usable for sighted people scanning the page. A website with large, straightforward-to-read text is more accessible to people with low vision and more usable for people reading on a phone in bright sunlight. But they are not the same thing, and a website can fail at one while succeeding at the other.
Why businesses and organizations care about accessibility
Many websites are legally required to be accessible. In the United States, the ADA applies to websites of government agencies and businesses that serve the public. The Department of Justice has brought lawsuits against companies whose websites were not accessible. In the European Union, the European Accessibility Act requires websites and mobile applications of public sector bodies to meet WCAG 2.1 Level AA by 2025. Canada, Australia, and many other countries have similar laws.
Beyond legal requirements, accessible websites reach more people. About one in four adults in the United States has some type of disability — that includes people who are blind, deaf, have limited mobility, have cognitive disabilities, or have temporary disabilities like a broken arm. Making a website accessible means those people can use it, shop on it, read it, and interact with it. For a business, that means more customers. For a government agency, that means serving all residents equally.
Accessibility also improves a website for everyone. Captions on videos help people in noisy places and people learning English. Keyboard navigation helps people who prefer not to use a mouse. Clear language and good structure help people with cognitive disabilities, people learning the language, and people reading on a small screen. A website built to be accessible is usually faster, more mobile-friendly, and easier to search.
How to check if a website is accessible
You can test a website's accessibility yourself using free tools. The WAVE browser extension (available for Chrome and Firefox) highlights accessibility problems on any page you visit — missing image descriptions, poor contrast, missing form labels. The Lighthouse tool, built into Chrome's developer tools, runs an accessibility audit and shows you which elements are failing. The axe DevTools extension does similar work and is free for basic use.
You can also test manually. Try navigating a website using only your keyboard — press Tab to move between elements, Enter to set up buttons, and arrow keys to navigate menus. If you cannot reach every interactive element or cannot tell which element is selected, the site has keyboard navigation problems. Try enlarging the text to 200 percent — if the layout breaks or text becomes unreadable, that is an accessibility problem. Try turning off images in your browser — if you cannot understand the page without them, the images need descriptions.
If you use a screen reader, you can test how a website sounds. NVDA (NonVisual Desktop Access) is a free screen reader for Windows. VoiceOver is built into macOS and iOS. JAWS is a paid screen reader widely used by people who are blind. Testing with an actual screen reader shows problems that automated tools miss, like confusing content order or buttons that do not announce their purpose clearly.
The connection to your device's built-in accessibility features
The accessibility features built into your computer and phone — screen readers, magnification, high contrast modes, captions — only work well if the websites and apps you visit are built accessibly. If a website ignores accessibility standards, your screen reader will struggle to navigate it, your magnification will break the layout, and your captions will not appear. The built-in tools on your device are only as useful as the websites that support them.
This is why web accessibility matters to you personally, whether or not you have a disability. If you use your phone's dark mode, you are relying on websites that respect color contrast standards. If you enlarge text on a website, you are relying on the site being built with flexible layouts. If you use captions on a video, you are relying on the creator to have added them. Web accessibility is the foundation that makes your device's accessibility features actually work.
Frequently Asked Questions
Is web accessibility the same as mobile-friendly design?
No, but they overlap. A mobile-friendly website works on small screens and with touch. An accessible website works with screen readers and keyboards. A website can be mobile-friendly but not accessible (it looks good on a phone but does not work with a screen reader), or accessible but not mobile-friendly. The best websites are both.
Do all websites have to be accessible by law?
In the United States, government websites and websites of businesses serving the public must meet accessibility standards under the ADA. Private websites not open to the public have fewer legal requirements, though this is still evolving. In Europe, public sector websites must be accessible. Other countries have different rules. Check your local laws or consult a lawyer if you are unsure.
Does making a website accessible cost a lot of money?
Building accessibility into a website from the start costs less than adding it later. If a website is already built, retrofitting it can be expensive depending on how many problems exist. But many accessibility improvements are straightforward — adding image descriptions, labeling form fields, fixing color contrast — and can be done without major redesigns.
Can I test a website's accessibility without special tools?
Yes. Try using only your keyboard to navigate, enlarge the text to 200 percent, turn off images, or use your device's screen reader. These manual tests reveal real problems. Automated tools like WAVE and Lighthouse catch many issues but not all — some accessibility problems only show up when a real person with a disability tries to use the site.
What should I do if a website is not accessible?
Contact the website owner and describe the problem — for example, "I cannot navigate this page using only a keyboard" or "The images have no descriptions." Many organizations want to fix accessibility problems but do not know they exist. If it is a government or business website and the problem is not fixed, you may be able to file a complaint with your local disability rights organization.