Autonomous System Number, what are they and why I use them. Where is the IP number from, and who manages the routing. What kind of IP number is it?

Trying to determine if connections made to provided on-line Internet services are from 'real' users can be quite a challenge. Loads of data center visits show that they are scrappers, hackers and or gathering data for SEO analysis. All this traffic is not wanted here. So to be able to filter inbound connections, I needed to know what kind of IP address type it is, and fast. If a visiting IP address is a data center then notify them that they are not welcome. All information, services and tools on this web site are intended for people, not automated systems. And thus this local IP address analysis service came to be. You are welcome to use it to find out about IP address information. An API is also available for remote automation lookup, however if you use the API, please limit your queries to one per second.

Enter an IPv4 network address

Find who is responsible for routing this IP address, the Autonomous System Number, name, location and more info about the entity.

Country ...
Region ...
City ...
Type ...
IP Range ...
ASN ...
Name ...
URL ...
Description ...
  • (CDN) Content Delivery Network
  • (COM) Commercial
  • (DCH) Data Center/Web Hosting/Transit
  • (EDU) University/College/School
  • (GOV) Government
  • (ISP) Fixed Line ISP
  • (LIB) Library
  • (MIL) Military
  • (MOB) Mobile ISP
  • (ORG) Organization
  • (MIL) Military
  • (RSV) Reserved
  • (SES) Search Engine Spider

Free IP to ASN API

A free IP address to ASN lookup API. Use it, but don't abuse it. This service runs on a no budget mini-computer with limited capacity, aggressive or bad use may lead to IP blocking. Don't request more than once a second please.

Updates to the local database are randomly undertaken, this means that maybe not all recent new routing assignments are known.

Easy to use straight forward API
The only parameter needed is a valid IPV4 IP address.

Example output of the IP to ASN API Example output of the IP to ASN API

The API returns JSON formated data

  • ipstart ASN IP address start of range
  • ipend ASN IP address end of range
  • 33915 the official ASN registration number
  • cnt two digit ASN country code
  • cntname ASN country name
  • cntstate ASN state, province or county
  • cntcity ASN city
  • name ASN name
  • controltype ASN IP range type (See legend)
  • url ASN contact URL
  • description ASN description