Free tool

Proxy Checker

Paste one proxy or a whole list. For every line our checker opens a real connection through the proxy to a public what-is-my-IP service and reports what the other end sees: the exit IP, city, ISP and ASN, and how long the round trip took. Then export the ones that work.

How the check works

A scheme at the start of a line (http://, https://, socks4://, socks5://) sets the protocol for that line; otherwise the menu above decides, and Auto tries HTTP CONNECT, then SOCKS5, then SOCKS4. If nothing answers on the port at all, the line fails straight away instead of waiting on every protocol. Latency is the full round trip through the proxy: connect, tunnel, TLS and one request to the lookup service, so a carrier network will read higher than a datacenter by design.

What a good result looks like

For a mobile line the ISP should be AT&T, T-Mobile or Verizon and the city should match the metro you bought; working lines on a US carrier are marked "Working · mobile". Run the list twice while holding a sticky session and the exit IP should stay the same. If HTTP fails but SOCKS5 works, your tool simply needs the SOCKS5 port.

Deeper checks

For fingerprint, bot-detection and leak tests on the same connection, IPFighter's free tools pair well with this checker:

IP score & lookup ↗ Browser fingerprint ↗ Bot detection ↗ DNS leak test ↗ WebRTC leak test ↗

Credentials are used for the check and are never logged or stored. Up to 200 lines per run, four at a time, and up to 200 checks per address per ten minutes. Private and internal addresses are refused.

Need a proxy that passes this test?

Real US carrier SIMs in eight metros, HTTP(S) and SOCKS5 on every line. Plans from $2 for 2 hours or $4/day.

View plans Check my IP