API

Free, no sign-up. Fair use, up to 60 lookups of other IPs per minute.

$ curl iptaster.com
# just your IP address

$ curl iptaster.com/ip
# the same for any client, browsers included

$ curl iptaster.com/json
# your IP with location, ASN and hostname

$ curl "iptaster.com/json?ip=8.8.8.8"
# details of any IP address