Check one proxy

Check whether a proxy is alive and get its protocols, anonymity grade, latency and location. Free, no key, CORS enabled. Each request runs a real live test against the proxy (a dead one can take a few seconds to report).

Two limits apply, and every checker endpoint shares them. Requests: 120 in a burst per IP, then 5 a second. Proxies checked: 300,000 a day per IP, refilling continuously. A signed-in account, or an API key, gets ten times both. Past either you get a 429 with Retry-After and a code saying which limit it was (rate_limited, daily_budget, or busy when the whole service is at capacity). Every answer reports the daily budget in X-RateLimit-Limit, X-RateLimit-Remaining and X-RateLimit-Cost, so you can pace yourself from the headers.

status is the verdict: alive, dead, invalid (we could not read the line), unresolved (the hostname has no DNS answer), forbidden (a private or reserved address we do not dial) or unchecked (no answer inside the time budget; not a verdict, retry the line). For a gateway proxy, exit_ip is where your traffic actually comes out, and the location fields describe that address. A dead proxy carries the reason in failure (refused, timeout, tls_error, bad_status, no_echo). Geo and ASN fields fill in when enrichment data exists and are null otherwise.