This VPN test tool will check an IP address for a known VPN/proxy connection. Test if your IP is anonymous or belongs to your ISP. The tool accepts IPv4 and IPv6 addresses.
Every IP address has information associated with it - carrier, ISP or block owner, and potentially public services available on that IP. This tool will test some of those metrics against known VPN and proxy fingerprints.
Data is provided by the awesome blackdotsh at getipintel.com who takes great pride in accuracy of results. VPN and proxy IP address assignments can change very often so the database is updated regularly.