API

All /ip* endpoints return the IP address of the requesting client, as seen by fst.st. They're useful for testing scripts, proxies, or network setups.

Endpoints

Path Format Response
/ip text/plain Just the IP address as text.
/ip.txt text/plain identical to /ip.
/ip.json application/json The IP address as JSON.
/ip.html text/html The IP address in a minimal HTML document.

An unknown file extension (e.g. /ip.xml) gets a 406 Not Acceptable response.

Rate limit

All /ip* endpoints are limited to 60 requests per 60 seconds per client IP (fixed window). Exceeding the limit gets a 429 Too Many Requests response with a Retry-After header (seconds until the next window). Other endpoints such as /version.json or /candidate-urls are not affected.