ATAG audits:
worth your while ๐Ÿ”Ž

Practical tips and examples to get started
Thibaud Colas @ FOSDEM 2025

Why weโ€™re here

Standards, authoring tools, accessibility by default

95.9% of home pages have accessibility issues

Line chart of WCAG non-conformance percentage from 2019 to 2024. The line goes starts slightly below 100% non-conformance in 2019, and barely goes down year to year.
Percentage of home pages with detected WCAG conformance failures over time. 2024 WebAIM Million

We need accessibility standards

  • WCAG: Web Content Accessibility Guidelines
  • ATAG: Authoring Tool Accessibility Guidelines
    • โ˜๏ธ Our focus today
  • UAAG: User Agent Accessibility Guidelines
  • WAI-ARIA: Web Accessibility Initiative โ€“ Accessible Rich Internet Applications
  • EN 301 549: Accessibility requirements for ICT products and services

We need authoring tools

We need support for social media posts. Blogging. Apps. Videos. Slides. Livestreams. Chat. Crafting HTML by hand is possible but error-prone.

Authors need:

  • Assistance
  • Documentation
  • Templates
  • Quality control
  • Accessible defaults

Authoring Tool Accessibility Guidelines (ATAG) 2.0

Version 2.0 in 2015

ATAG example: in a Content Management System (CMS)

Screenshot of the Wagtail 6.3 page editor, with a sidebar to the left, an editing form, and to the right a preview panel with a dark theme web page
Wagtail v6.3 page editor, with page preview opened

ATAG in practice: Part A

My highlights โ€“ things that go far beyond WCAG ๐Ÿš€

Part A: Make the authoring tool user interface accessible

Documenting features: for developers and for users

Screenshot of the Wagtail user guide website homepage. Features a navigation sidebar to the left, and page content listing sections to the right: getting started, how-to, concepts
Wagtail user guide homepage

Docs coverage for devs: 80%. For editors: 52 of 145 features (35%)

ATAG in practice: Part B

To infinityโ€ฆ and beyond WCAG! ๐ŸŒˆ

B.1. Fully automatic processes produce accessible content

Screenshot of the DSF membership nomination form, with a number of fields, including email and Your name
Google Forms, with no autocomplete attribute support

B.2.3. Assist authors with managing alternative content for non-text content

(as in โ€“ help people creating alt text (and captions))

Screenshot collage of Mastodon. To the left the post editor, with in-progress content including an image. There is a warning triangle with the word 'Alt' in yellow. To the right, the interface to edit images, with a multiline text field: 'Describe for people who are blind or low-vision'. There is also a 'Detect text from picture' button below
Mastodon alt text UI

B.2.4. Assist authors with accessible templates

B.3.1. Assist authors in checking for accessibility problems

Sa11y accessibility checker widget, over a blog page. The widget spotted a heading error, and displays alt text for manual review
Sa11y accessibility checker widget

B.3.2. Assist authors in repairing accessibility problems

Example: alt text

Bar chart comparing Wagtail AI vs. existing alt text quality, based on 441 homepages, scored by the accessibility team. Real-world alt text scores low. AI alt text scores higher, with 49% of AI alt texts scored 5/5 compared to 8% for real-world

B.3.2. example implementation

Screenshot of the Wagtail Upload images interface. It says 3 images were uploaded successfully, and offers three different options to fill the description field
Image upload with AI-generated descriptions

Get started

Prerequisites

(which you can arrive at iteratively)

  1. Good documentation of project features
  2. Good demo setup to test said features
  3. (Some) knowledge of ATAG
  4. Report format

And thatโ€™s it! ๐ŸŽŠ ๐Ÿ‘€

Report templates

ATAG Report Tool

Screenshot of the WAI ATAG Report Tool interface, Overview page, with existing report under way in sidebar
W3C Web Accessibility Initiative (WAI) report tool

Authoring Tools List

Screenshot of the WAI Authoring Tools list
W3C Web Accessibility Initiative (WAI) authoring tools list

Beyond WCAG and ATAG

Thank you! โค๏ธ

Come say hi and ask questions?

Progress for Wagtail

Conformance Level ATAG Part A Part B
Pass 28 (+6 ๐ŸŽ‰) 14 (+2 ๐Ÿค˜) 14 (+4 ๐Ÿš€)
Fail 24 (-6) 15 (-2) 9 (-4)
Not applicable 13 4 9
Wagtail 6.3 audit findings at the success criteria level