Accessibility TestingReference
Severity Levels
What Critical, Serious, Moderate, and Minor mean in a TestKase scan.
Severity Levels
Every accessibility issue is labeled with one of four severity (impact) levels. The labels come from axe-core's impact system — they indicate how much of a barrier the issue is, not how hard it is to fix.
API note — in TestKase's REST and webhook payloads the field is named
impact(matching axe-core's wire format). The TestKase UI and these docs use the human-friendly term severity. Same four buckets either way:critical,serious,moderate,minor.
The four levels
| Level | Meaning | Example |
|---|---|---|
| Critical | Blocks users with disabilities from core functionality | A form submit button with no accessible name |
| Serious | Major barrier; most affected users can work around with effort | Color contrast failing AA by a large margin |
| Moderate | Usability issue; causes friction but rarely blocks | Inconsistent heading order |
| Minor | Polish item; very rarely user-blocking | Missing lang on <html> when language is obvious |
How to use severity
- Fix Critical first. One critical finding often blocks entire user journeys.
- Sweep Serious. These are the bulk of most reports — color contrast, missing labels, keyboard traps.
- Batch Moderate. Assign these to a team and fix in a cleanup sprint.
- Triage Minor. Fix when you're in the same code, but don't block releases.
What severity does not tell you
- Frequency — a minor issue on every page may matter more than a critical issue on a seldom-visited page. Cross-reference with the affected-pages table.
- Your users — severity is generic. If your user base skews toward a specific disability, weight accordingly (e.g., screen-reader users make keyboard issues more critical than the default labels suggest).