Web accessibility (WCAG)
What is web accessibility (WCAG)?
Web accessibility is the property of a site that lets people with disabilities use it — with a screen reader, by keyboard alone, with low vision or without sound. It is measured against WCAG, a set of testable criteria at three levels (A, AA, AAA), of which AA is the usual requirement. It covers contrast, image alternatives, field labels, focus order and captions.
Example
An enquiry form with five fields. The labels are grey on white at a contrast of 2.8:1, where WCAG asks for at least 4.5:1 on body text. The fields have no label, only placeholder text that disappears at the first keystroke; a placeholder is not a label, and WCAG asks for a caption that stays visible while the field is filled in and checked. The error is a red border with no words, which tells a person who does not distinguish red only that something, somewhere, is wrong.
The repairs are small: contrast at 4.5:1 (3:1 for large text), a visible label above every field, a focus outline that follows the Tab key, and the error written beside the field that caused it. None of them changes the design; they change whether the form can be completed at all.
WCAG arranges its criteria under four ideas — perceivable, operable, understandable, robust — at three levels. Level A is the floor, AA is what regulation and procurement normally ask for, and AAA is stricter than most sites can hold across all their content.
Why it matters for a business
The people who cannot use a mouse, or who read at 200% zoom, rarely complain. They leave, and nothing in the analytics says why. The same repairs help everyone else: captions get watched without sound, high contrast survives sunlight on a phone, and a form that works by keyboard is faster for anyone filling in forms all day.
There is a legal side too. Public-sector sites have had accessibility obligations under a 2016 EU directive, and since 28 June 2025 the European Accessibility Act covers a list of private services, e-commerce among them. The European benchmark is the standard EN 301 549 — WCAG 2.1 level AA today, WCAG 2.2 in its new edition.
Contrast, labels, focus and heading structure are part of how we build pages in website development. A full WCAG audit and bringing an existing site into conformance are separate work we take on, outside a standard build.
What to ask
- To which level — A, AA or AAA — and against which version, WCAG 2.1 or 2.2?
- Was it checked by keyboard and with a screen reader, or only by an automated tool? Tools catch part of the criteria; the rest needs a person.
- Does every image that carries meaning have a text alternative?
- Can the form, or the order, be completed with the keyboard alone?
- Is there an accessibility statement and an address for reporting a problem?
- Who keeps new content accessible after launch?