How we test

1. In short

Luentis checks websites against WCAG 2.2 level AA, the basis of EN 301 549 and so of the European Accessibility Act. Only parts of it can be checked automatically. So we say exactly what we measure, and guide you through the rest.

• WCAG 2.2 AA has 55 success criteria.
• We check 26 of them automatically, fully or in part.
• 29 can only be judged by a person. The guided manual check is there for those.

An audit with Luentis is not a certification and does not confirm conformance.

2. What we check automatically

axe-core. Every page is loaded in a real browser (Chromium) and checked with axe-core, an open and widely used testing library. We use its rules for WCAG 2.0, 2.1 and 2.2 at levels A and AA. With them we check 23 success criteria fully or in part, for example text alternatives, contrast, form field labels, headings and the language of the page.

Our own checks. For some criteria that axe-core does not cover, we wrote our own checks:

• Keyboard trap (2.1.2): we move through the page with the Tab key and check that focus never gets stuck.
• Visible focus (2.4.7): for every element you can reach, we check that something visibly changes when it gets focus.
• Reflow (1.4.10): we open the page 320 pixels wide, like 1280 pixels at 400 % zoom, and look for content that sticks out to the side.
• Text spacing (1.4.12): we increase line, paragraph, word and letter spacing as the criterion describes and look for text that gets cut off.
• Audio that plays by itself (1.4.2): we look for audio and video that starts with sound on its own.
• Captions (1.2.2): we look for videos without a caption track.

These checks run on up to 25 pages per scan, on one page per section of the website, because pages in a section usually share a template.

3. How a scan works

• Free scan: the home page, on desktop (1280 pixels wide) and on mobile (390 pixels wide).
• Single audit: up to 250 pages, each on desktop and on mobile. We find the pages through the sitemap and links on the website.
• Languages: if the start page sits under a language path such as /en/, we check the pages in that language first. Other languages are only added if there are pages to spare, because they usually share the same templates.
• Consideration: our scanner identifies itself as "LuentisBot", visits at most one page per second and respects the website's robots.txt, except for the start page you gave us. We do not check pages behind a login. More on the page about LuentisBot.

4. How we order the results

• By rule and template: the same error on 80 product pages is usually one error in one template. So we show it once, with the number of pages and places affected.
• Severity: critical, serious, moderate or minor, as rated by axe-core and by us for our own checks. Severity is always shown as a word and a symbol, never by colour alone.
• Fixes: for every error we explain who it affects and how to fix it, often with a code suggestion. Code suggestions are suggestions you should check.
• Score: every group of errors lowers the score by its severity (critical 10, serious 5, moderate 2, minor 1). The total is turned into a scale from 0 to 100: 100 × e^(−total / 50). The score only covers what can be checked automatically and does not measure conformance.

5. "To check by hand"

Sometimes axe-core cannot judge a place with certainty, such as text on a background image where the contrast cannot be measured. We show these places separately as "to check by hand". They are not errors, but they have not passed either. A person has to look at them.

6. What only a person can judge

29 of the 55 criteria cannot be checked automatically at all, and even for the others a machine does not find everything. Whether an alt text describes an image well, whether an error message is clear or whether the reading order makes sense can only be said by a person.

7. Guided manual check and statement

With the single audit you get a guided manual check. It goes through the criteria we do not check automatically, explains each question in plain language and tells you how to test it. Your answers are stored with the date and the name of who answered.

From the results Luentis drafts an accessibility statement based on the EU model. You review, change and publish the draft yourself.

8. What Luentis is not

• Not a certification, not a seal and not a confirmation of conformance.
• Not legal advice.
• Not an overlay: we do not offer a widget that is meant to cover up errors on your website. Errors are fixed in the website's code.

9. Where the data is

The scanner, the app and the data run in data centres in the EU, in Frankfurt am Main. More in the privacy policy.