I built this because I got tired of pricing pages. Every IP intelligence API I looked at was either 200 dollars a month to start, or a free tier that dies after 14 days. For a side project checking a few hundred signups a week, that is absurd. So Maskbreak is free. 1,000 requests an hour, every signal, no card, no expiry. You POST an IP and get back whether it is a VPN, a proxy, a Tor exit or a datacenter range, plus a 0-100 score and an allow/review/block verdict. You can try it in a terminal right now without signing up for anything: curl -X POST https://maskbreak.com/api/lookup \ -H 'Content-Type: application/json' -d '{"ip":"185.220.101.1"}' Two things I did differently from most of these. Datacenter alone scores 40, which comes back as "review", not "block". A lot of legitimate traffic comes out of datacenters and blocking all of it is lazy. VPN and datacenter are separate flags. Most VPN exits sit in datacenters, so if you collapse those into one signal you lose the thing you actually wanted to know. What the IP check alone will not do is catch someone on a clean home IP running an antidetect browser. For that there is a browser SDK that reads the device side, also free, but it is a second thing to install rather than one curl. I would rather hear where it gets things wrong than where it gets things right. If you have an IP you know the answer for, paste it in and tell me if the verdict is off.

Maskbreak

Free fraud detection API. 1,000 requests an hour, no card.

Free fraud detection API. 1,000 requests an hour, no card.