What is Web Accessibility? Complete Beginner's Guide

Web accessibility is about making the internet usable for everyone – regardless of ability. It may sound obvious, but the reality is that millions of people are excluded from digital services every day due to poor accessibility.

Globally, over one billion people live with some form of disability. When websites aren't accessible, they exclude a significant portion of the population from shopping, communicating, and participating in society.

This guide gives you the fundamentals you need to understand web accessibility – what it is, why it matters, and how you can start making your digital products accessible to everyone.

What does web accessibility mean?

Web accessibility (abbreviated a11y) means that websites, tools, and technologies are designed and developed so that people with disabilities can use them.

More specifically, it means people can:

Accessibility isn't just about 'blind people using the site.' It encompasses a broad group of people with different needs – from permanent disabilities to temporary injuries like a broken arm, to situational limitations like using a phone in bright sunlight.

Why is accessibility important?

There are three main reasons to invest in web accessibility:

1. It's the right thing to do

The internet has become a fundamental part of society. Banking, government services, shopping, social interaction – it all happens online. Excluding people from this is a form of discrimination.

2. It's the law

From June 2025, the European Accessibility Act applies to private sector in the EU. E-commerce, banks, transport services, and much more must meet WCAG 2.1 AA standards. Violations can lead to fines up to €10 million.

3. It's good for business

Accessibility is not a cost – it's an investment that pays off through greater reach and reduced risk.

Who needs accessible websites?

Accessibility benefits more people than you might think:

People with visual impairments: Includes blind users who use screen readers, people with low vision who need zoom or high contrast, and color-blind users who can't rely solely on color for information.

People with hearing impairments: Need captions on video, transcripts of audio, and visual alternatives to audio signals.

People with motor disabilities: Can't use a mouse and rely on keyboard, voice control, or specialized assistive devices. Need sufficiently large click targets and clear focus indicators.

People with cognitive disabilities: Includes dyslexia, ADHD, memory difficulties, and learning disabilities. Need clear structure, simple language, and consistent design.

Temporary disabilities: A broken arm, eye infection, or concussion means anyone might temporarily need accessibility features.

Situational limitations: Sunlight on screen, noisy environment, or holding a baby in one arm – all create temporary needs for better accessibility.

The four core principles (POUR)

WCAG (Web Content Accessibility Guidelines) is the international standard for web accessibility. It's built on four principles, summarized as POUR:

1. Perceivable

Information and interface must be presented in ways users can perceive with their senses.

2. Operable

Users must be able to interact with the interface.

3. Understandable

Information and interface must be comprehensible.

4. Robust

Content must be robust enough to be interpreted correctly by various user agents, including assistive technologies.

Common accessibility barriers on the web

Here are the most common problems that make websites inaccessible:

Images without alt text: Screen readers can't describe what an image shows if the alt attribute is missing or empty.

Insufficient color contrast: Light gray text on white background is hard to read for many – not just visually impaired users.

Forms without labels: Screen readers need elements to explain what each field should contain.

Not keyboard navigable: Dropdown menus and modals that only work with mouse exclude keyboard users.

Video without captions: Deaf users can't access video content without text.

Auto-playing media: Audio that starts automatically interferes with screen readers and can trigger anxiety in sensitive users.

Inconsistent navigation: When menus and buttons move around between pages, it becomes difficult for users with cognitive disabilities.

How to get started with accessibility

Making a website accessible can feel overwhelming, but you don't have to do everything at once. Here's a practical starting guide:

Step 1: Scan your site

Use an automated tool like Xrayd, Lighthouse, or WAVE to find obvious problems. Automated tools catch about 30-40% of accessibility issues.

Step 2: Prioritize critical issues

Focus first on problems that completely block users – e.g., forms that don't work with keyboard or checkout flows missing labels.

Step 3: Test manually

Navigate through the site using only keyboard (Tab to move focus, Enter to click). Test with a screen reader if possible.

Step 4: Involve users

Nothing beats having people with disabilities test your site. They find problems you'd never think of.

Step 5: Build accessibility into your process

Add accessibility requirements to your Definition of Done. Make it part of code reviews and QA.