ipify
Developmentapi.ipify.org
A minimal public IP address API: returns the caller's own public IPv4 address, or the address seen on a dual-stack endpoint, as JSON.
Capabilities (2)
GET /v1/data/ipify/public-ip-dual-stack1 creditReturns the caller's public IP address over a dual-stack endpoint, so an IPv6-capable client sees its IPv6 address and an IPv4-only client still gets its IPv4 address.
GET /v1/data/ipify/public-ipv41 creditReturns the caller's public IP address as seen by ipify, in a JSON object with an ip field.
Licence
ipify publishes no data licence, because it publishes no third-party data: the only content of a response is the caller's own IP address, which is not ipify's to license. The site makes three relevant statements: "You can use it without limit (even if you're doing millions of requests per minute)", "No visitor information is ever logged. Period.", and "ipify is completely open source" (the server implementation is on GitHub). There is no copyrightable dataset here and no restriction is placed on use, so commercial use is recorded true; redistribution is also recorded true in the sense that nothing is withheld, though the response is specific to the calling client and there is no upstream corpus to redistribute. No attribution is requested and none is claimed.
https://www.ipify.org/Attribution
Display this wherever you show the data. It arrives on every response as provenance.attribution_text.
Public IP address as observed by ipify (api.ipify.org). No attribution required.
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