FDN (Fast Detection Network) is a minimalist IP detection and geolocation service for developers, network admins and automation scripts.
- Terminal native: no API key and no signup. Just
curl -s fdn.io. - Blazing fast: edge-powered responses in under 50 ms, served from CDN nodes close to you.
- Developer friendly: plain text by default, clean JSON when you need it. Works with curl, wget and httpie.
Endpoints:
| Endpoint | Response |
|---|---|
fdn.io |
Your public IP address |
fdn.io/v4 |
IPv4 address only |
fdn.io/v6 |
IPv6 address only |
fdn.io/json |
Full JSON with all fields |
fdn.io/city |
City name |
fdn.io/country |
Country name |
fdn.io/timezone |
Timezone identifier |
fdn.io/isp |
ISP name |
fdn.io/loc |
Latitude, longitude |
fdn.io/{ip} |
Lookup any IPv4 / IPv6 address |