About Accessio
Accessio is a web-based accessibility diagnostic tool for websites. Users can submit a site URL to run a free automated test without creating an account. The service states that its checks are based on axe-core and aligned with RGAA 4.1, WCAG 2.1 level AA, and EN 301 549. It highlights common issues such as color contrast, missing alt text, unlabeled form fields, heading structure problems, invalid ARIA attributes, and missing page language declarations. The site is explicit that automated testing covers only part of accessibility requirements and does not replace a human audit for full compliance assessment.