503 Service Unavailable

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?

503

Service Unavailable

Server error · RFC 9110

The server is temporarily unable to handle the request. Include Retry-After when possible.

When to use

Deployments, overload, maintenance, dependency outage you expect to pass.

Don’t

A bug is 500. A dead upstream with a bad packet is 502. Rate limiting a client is 429.

Live URL

curl -i https://corecoding.com/utilities/http-status.php?code=503


    

Code use cases