IP Address Lookup

What a String of Four Numbers Actually Tells You

An IP address looks like 104.26.12.54 — four numbers that seem to tell you nothing. But behind every IP address is a registration record: which organisation controls this address block, what country it's allocated to, which autonomous system it belongs to. From these records, geolocation databases infer probable location, ISP, and network type. This tool queries those databases and surfaces the information in seconds.

Developers need this for debugging. When a production request fails, knowing whether it came from a cloud provider IP, a residential ISP, or a known VPN range changes the diagnosis. When a webhook doesn't arrive, knowing what ISP or ASN the sending IP belongs to helps verify whether it's a legitimate source.

Understanding Geolocation Accuracy Limits

IP geolocation is probabilistic, not definitive. Country-level accuracy is excellent — above 95% for most regions — because large blocks of addresses are allocated to specific countries. City-level is murkier: 70–80% for residential ISPs, less for mobile carriers (which may assign IPs registered to headquarters in a different city), and essentially meaningless for cloud provider IPs (which geolocate to the data centre, not the customer's location).

The coordinates this tool returns are the centroid of the IP block's registered location, not GPS coordinates of the device. They're useful for country and region-level routing decisions, not for physical location of users.

ASN — The Network Identity Behind an IP

The Autonomous System Number is often more informative than the geolocation. An ASN tells you which organisation controls the IP block. AS15169 is Google. AS16509 is Amazon Web Services. AS14061 is DigitalOcean. Residential ISPs have their own ASNs — AS18101 is Reliance Jio, AS9829 is BSNL. VPN providers, CDN networks, and threat actors all have distinctive ASNs that experienced security teams recognise immediately.

For API security and abuse detection, checking whether request IPs belong to cloud provider ASNs (where no legitimate consumer should live) or known proxy/VPN ASNs is a powerful signal. A "user" request from an AWS IP range is almost certainly automated.

Engineering Use Cases

• Debugging API access issues: When a client reports they can't reach your API, look up their IP to understand whether the problem is geographic restriction, ISP-level blocking, or CDN routing.
• Webhook source verification: GitHub, Stripe, Twilio, and most webhook providers publish their sending IP ranges. Look up the IP in your webhook logs to verify it belongs to the expected provider's ASN.
• Server configuration testing: After deploying to a new hosting provider, look up your server's IP to confirm it geolocates to the expected region — relevant for latency, data residency compliance, and CDN configuration.
• Geofencing development: Test your IP-based geofencing logic by looking up IPs from different regions and verifying the location data your implementation receives. Construct test request URLs with the URL Encoder.
• Security incident analysis: When reviewing server access logs after an incident, look up suspicious IPs to understand whether they belong to known threat infrastructure, cloud providers, or residential ISPs.

Your IP vs a Looked-Up IP

The tool shows your current public IP automatically on load. This is what every server on the internet sees when you make a request — not your local network IP (192.168.x.x) which is only visible within your home or office network. If you're using a VPN, the public IP shown is your VPN exit node's IP, not your ISP's IP. If you're behind a corporate proxy, the shown IP is the proxy's IP. This is why websites see a different location than your physical location when you use a VPN.

✓Verified by ToollyX Team · Last updated June 2026