IP Lookup
IP address lookup — geolocation, reverse DNS, ASN, network block, and RDAP registration for public IPv4 and IPv6.
- IP
216.73.217.10- Version
- IPv4
- Public
- Yes
- Reverse DNS
- —
- Country
- US
- Location
- Columbus, Ohio
- ASN / Org
- AS16509 Amazon.com, Inc.
- Network block
-
216.73.192.0 – 216.73.219.255 (7,168 addresses)
Registration (RDAP)
- Network
- AWS-ANTHROPIC
- Handle
- NET-216-73-216-0-1
- Range
- 216.73.216.0 – 216.73.219.255
- Type
- ASSIGNMENT
- Organization
- Anthropic, PBC
- Registered
- 2024-06-05 UTC
- Updated
- 2024-06-05 UTC
- Status
- active
- Abuse contact
- [email protected]
Raw RDAP JSON
{
"arin_originas0_originautnums": [],
"cidr0_cidrs": [
{
"v4prefix": "216.73.216.0",
"length": 22
}
],
"endAddress": "216.73.219.255",
"entities": [
{
"entities": [
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-08-18T02:54:11-04:00"
},
{
"eventAction": "registration",
"eventDate": "2023-07-31T16:45:12-04:00"
}
],
"handle": "ANTHR5-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/ANTHR5-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/ip/216.73.216.194"
},
{
"href": "https://whois.arin.net/rest/poc/ANTHR5-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/ip/216.73.216.194"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"technical",
"routing",
"administrative",
"noc",
"dns",
"abuse"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "548 Market St.\nPMB 90375\nSan Francisco\nCA\n94104-5401\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"Anthropic"
],
[
"org",
[],
"text",
"Anthropic, PBC"
],
[
"kind",
[],
"text",
"group"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-415-236-0599"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2023-08-22T17:10:25-04:00"
},
{
"eventAction": "registration",
"eventDate": "2023-07-31T16:51:11-04:00"
}
],
"handle": "AP-2440",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/AP-2440",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/ip/216.73.216.194"
},
{
"href": "https://whois.arin.net/rest/org/AP-2440",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/ip/216.73.216.194"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"registrant"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"fn",
[],
"text",
"Anthropic, PBC"
],
[
"adr",
{
"label": "548 Market St.\nPMB 90375\nSan Francisco\nCA\n94104-5401\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"kind",
[],
"text",
"org"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2024-06-05T12:42:32-04:00"
},
{
"eventAction": "registration",
"eventDate": "2024-06-05T12:42:32-04:00"
}
],
"handle": "NET-216-73-216-0-1",
"ipVersion": "v4",
"links": [
{
"href": "https://rdap.arin.net/registry/ip/216.73.216.0",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/ip/216.73.216.194"
},
{
"href": "https://whois.arin.net/rest/net/NET-216-73-216-0-1",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/ip/216.73.216.194"
},
{
"href": "https://rdap.arin.net/registry/ip/216.73.208.0/21",
"rel": "up",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/ip/216.73.216.194"
}
],
"name": "AWS-ANTHROPIC",
"notices": [
{
"description": [
"By using the ARIN RDAP/Whois service, you are agreeing to the RDAP/Whois Terms of Use"
],
"links": [
{
"href": "https://www.arin.net/resources/registry/whois/tou/",
"rel": "terms-of-service",
"type": "text/html",
"value": "https://rdap.arin.net/registry/ip/216.73.216.194"
}
],
"title": "Terms of Service"
},
{
"description": [
"If you see inaccuracies in the results, please visit: "
],
"links": [
{
"href": "https://www.arin.net/resources/registry/whois/inaccuracy_reporting/",
"rel": "inaccuracy-report",
"type": "text/html",
"value": "https://rdap.arin.net/registry/ip/216.73.216.194"
}
],
"title": "Whois Inaccuracy Reporting"
},
{
"description": [
"Copyright 1997-2026, American Registry for Internet Numbers, Ltd."
],
"title": "Copyright Notice"
}
],
"objectClassName": "ip network",
"parentHandle": "NET-216-73-208-0-1",
"port43": "whois.arin.net",
"rdapConformance": [
"nro_rdap_profile_0",
"rdap_level_0",
"cidr0",
"arin_originas0"
],
"startAddress": "216.73.216.0",
"status": [
"active"
],
"type": "ASSIGNMENT"
}
About this tool
Look up any public IP to see where it routes on the internet: reverse DNS hostname, country and city estimates, autonomous system and organization, the routed network range, and registry registration details when published.
What you get
- Normalized IP with IPv4/IPv6 version and public/private flag
- Reverse DNS (PTR) hostnames when published
- Country flag, region, city, ASN number, and ISP or organization name
- Network block (CIDR or start–end range) for the allocation
- RDAP registration summary — network name, dates, and abuse contact when available
How to use
Your public IP is prefilled on page load. Edit the field or replace it, then click Lookup.
Sample IP lookup report
A datacenter egress address might resolve to:
| Field | Value |
|---|---|
| IP | 198.51.100.42 |
| Reverse DNS | 42.100.51.198.in-addr.arpa → host.example.net |
| Country / city | Netherlands, Amsterdam |
| ASN / org | AS64496 Example Cloud Ltd |
| Network | 198.51.100.0/24 |
RDAP network registration details appear when regional data is available.
Glossary
- ASN
- Autonomous System Number — identifies the network operator routing the IP.
- rDNS
- Reverse DNS PTR record mapping an IP back to a hostname.
- RDAP (IP)
- Regional registry data describing allocation and abuse contacts.
FAQ
How to look up IP address geolocation and ASN?
Enter an IPv4 or IPv6 address to see country flag, city and region when available, ASN, organization, network range, and reverse DNS.
What is my public IP address?
Your current public IP is prefilled in the form on page load—submit it or replace with any address you want to investigate.
How to find ASN and ISP for an IP address?
Results show autonomous system number, ISP or company name, and the routed network block the address belongs to.
What is reverse DNS lookup?
Reverse DNS maps an IP to its PTR hostname—often reveals hosting provider naming patterns and mail server identity.
How accurate is IP geolocation?
Country and region are usually reliable; city is approximate for routing and analytics—not a precise street address or GPS fix.
Does IP lookup show RDAP network registration?
Yes—RDAP registration details from the regional registry appear alongside geo and ASN when available for the address range.
By using this tool you agree to our Terms of Use and Privacy Policy. Results are provided as-is without warranty.