What this tool calculates
The IP lookup validates an IPv4 or IPv6 string, identifies locally scoped private addresses, and requests best-effort metadata for public addresses. A successful public response can include country, region, city, network organization, time zone, and approximate coordinates when a provider supplies them.
This is network-registration and geolocation context, not a person's identity or precise device location. Multiple users can share one public address, mobile addresses can move, and a VPN or proxy can represent an exit server far from the user.
Inputs
Enter one complete IPv4 or IPv6 address. Hostnames, URLs, port suffixes, CIDR ranges, and free-form text are not accepted as a single-address lookup. The page can also inspect the connecting address exposed by the hosting platform for its automatic result.
Avoid sharing lookup results that contain operationally sensitive addresses. A public IP is not a password, but it can become security-relevant when combined with logs, timestamps, account data, or infrastructure details.
Method and formula
The endpoint first checks address syntax. Invalid text returns an INVALID_IP error. It then classifies private or locally scoped addresses without sending them to a geolocation provider. Such a response retains the address, marks isPrivate true and isFound false, and leaves public-location fields empty.
For a valid public address, the endpoint tries a bounded provider fallback chain and normalizes successful data into one response contract: IP, country, region, city, ISP or organization, time zone, latitude, longitude, private flag, and found flag. If all providers fail, it returns a temporary LOOKUP_FAILED response rather than invented data.
Worked example
Enter 192.168.1.8. This address belongs to the RFC 1918 private-use block 192.168.0.0/16.
The endpoint returns a successful classification with the original IP, private status, and no public country, city, ISP, or coordinates. It does not contact the public geolocation chain for that result. The absence of a city is expected: private addresses can be reused inside unrelated networks and have no unique global location.
By contrast, a syntactically impossible value such as 999.1.2.3 is rejected before lookup.
How to interpret the result
Country or network-organization data can support routing diagnostics, abuse triage, or localization defaults, but it should be treated as an estimate. “ISP” may name a hosting provider, corporate network, or carrier rather than the person using the connection. Coordinates commonly represent a city centroid or database location.
Private status means the address is intended for local scope under the implemented rules. It does not mean the device is trustworthy or secure. Network access decisions require authentication and authorization, not geolocation alone.
Accuracy and limitations
Provider databases change and can be stale, incomplete, or unavailable. Carrier-grade NAT, VPNs, relays, corporate gateways, and satellite networks weaken geographic inference. IPv6 privacy addresses can rotate. The lookup cannot identify a household, legal residence, precise street, or current physical position.
Do not use the result as the sole basis for fraud accusations, sanctions decisions, emergency response, or access denial. Apply data-protection rules, minimize retention, and provide a correction path when geolocation materially affects a user.
Sources
- RFC 1918: Address Allocation for Private Internets defines the familiar private-use IPv4 blocks used by the local classification example.
- RFC 4291: IPv6 Addressing Architecture defines IPv6 address structure and scopes.
- MaxMind GeoIP accuracy documentation explains why IP geolocation is probabilistic and not a precise-person locator.
Editorial record
Author: SoupCalc Editorial Team
Last reviewed: August 14, 2026
Review scope: IPv4/IPv6 validation, private-address short circuit, normalized response fields, failure behavior, privacy limitations, and the 192.168.1.8 example were checked.