How to complete the challenge `POST /heartbeat as Trace (501)`

By Alan RichardsonPublished 2026-07-31

Send a normal POST request to /heartbeat, but add this header:

X-HTTP-Method-Override: TRACE

The server treats the request as TRACE and returns 501 Not Implemented.

Try it now

Browser HTTP clients cannot send TRACE methods. The HTTP client below is closed by default because it cannot complete this challenge from the browser; try it for yourself to see.

POST /heartbeat with TRACE override to trigger 501

Experiment with this endpoint

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How to complete the challenge POST /heartbeat as Trace (501)

Try it now

How to complete the challenge `POST /heartbeat as Trace (501)`