All APIs support CORS and can be used on HTTPS with a protocol-relative url like so: //whats-my-ip.herokuapp.com/json?callback=alert.

Happy hacking!

Availability Notice

Heroku nerfed the free tier and now forces apps to to stay offline for a minimum of 6 hours per day. (Starting on August 15th.)

If you'd like this service to be available 24/7, please consider supporting me through Gratipay - $2/week would be enough to keep the service up for everyone:

What's My IP service by Nathan Friedly with node.js.

Fork me on GitHub