Look up a status, pick the right one for an API, or hit a live endpoint that actually returns it. Add ?code=418 to this URL and the response is that status — useful for curl, interceptors, and “what does my client do on 503?” Nothing here phones home except the Try it fetch to this same page.
Which class?
The server requires a conditional request (If-Match) to prevent lost updates.
When to use
APIs that insist on ETags for PUT/PATCH.
Don’t
When the condition was sent and failed, that is 412.
Live URL
curl -i https://corecoding.com/utilities/http-status.php?code=428
No codes match.
Code use cases