Errors
Interpret FOSSA API error responses, 4xx codes indicate client errors, 5xx codes indicate server-side issues.
1 min readUpdated Jul 9, 2026
Overview
The FOSSA API uses conventional HTTP response codes to indicate the success or failure of a request.
| Status range | Meaning | What to do |
|---|---|---|
2xx | Success | The request succeeded. |
4xx | Client error | Something about the request was wrong, for example, a missing API token or an omitted required parameter. Check your request and try again. |
5xx | Server error | An error occurred on FOSSA's servers. Retry later, and contact support if it persists. |
For the full list of HTTP status codes, see List of HTTP status codes.
Note
If you receive an unexpected error, contact support@fossa.com with the endpoint, request, and response you received.