# WorldIP.io

> Free, real-time IP intelligence — every IPv4 address, every range, every
> organization, every ASN, every country. Reverse DNS (PTR), with forward
> confirmation (FCrDNS), is continuously rescanned by a first-party global scanner
> fleet. A daily count of the domains hosted on each IPv4 address comes from
> issued.live's DNS data (issued.live is WorldIP's sister service for everything
> in front of an IP).
> Designed for engineers, SOC analysts, and AI assistants that need verifiable
> network-attribution data.

## MCP server (for AI assistants)

WorldIP speaks the Model Context Protocol, so an MCP-aware client can call it
as a tool instead of scraping pages.

- Endpoint: `https://worldip.io/mcp` (JSON-RPC 2.0 over HTTP POST)
- Tools: `lookup_ip(ip)` — full public profile for an IPv4 or IPv6 address (IPv4 includes
  `domains_hosted`, a daily count — never the names);
  `whats_my_ip()` — the caller's own address and profile
- No key required. Shares the keyless quota: 1,000 requests/day and 60/min per
  calling IP.

Add it to Claude Code in one line:

    claude mcp add --transport http worldip https://worldip.io/mcp

Or by hand in .mcp.json. Note the `type` field -- it selects the transport, and the
config will not work without it:

    { "mcpServers": { "worldip": { "type": "http", "url": "https://worldip.io/mcp" } } }

Note: `/mcp` is POST-only and returns 405 to GET — it is an API endpoint, not
a page, and is deliberately absent from the sitemap.

## Keyless JSON API

Every IP page also serves JSON directly — no key, no signup:

    curl https://worldip.io/8.8.8.8

Returns: ip, ptr, forward_dns (forward check of the PTR), domains_hosted (daily count of domains hosted on the
IP, from issued.live — a number, never the names), asn (number + name), org, country, region and city (where available,
otherwise null), cidr. Same 1,000/day + 60/min per-IP quota as the MCP tools.

IPv6 addresses work the same way:

    curl https://worldip.io/2001:4860:4860::8888

Same keys, plus version (6), address_type, prefixes (/32 /48 /56 /64) and an
rdns block. Most IPv6 reverse-DNS names are generated by the ISP from a
template; rdns.kind says isp_generated, wildcard or specific. VPN/proxy
detection, trust score, BGP and hosted domains are IPv4-only. An IPv4-mapped
address (::ffff:8.8.8.8) is answered as the IPv4 address it carries.

## Keyed API (beta)

Full IP profiles (VPN/proxy/Tor/datacenter classification, residential proxy
detection, trust score, BGP context and the hosted-domain count) come from the
keyed lookup, over HTTPS with the key in the Authorization header (never in the URL):

    curl -s https://worldip.io/api/v1/ext/lookup/8.8.8.8 -H "Authorization: Bearer YOUR_KEY"

Keys are in beta: issued free to customers of issued.live Plus (a Pro key) and
issued.live Pro (a Business key). Self-serve keys and paid plans are not open yet,
and limits may change during the beta. The MCP server above stays keyless.
Details: https://worldip.io/developers#beta-keys

## Core lookups

- [IP address](https://worldip.io/8.8.8.8): per-IP page — PTR hostname, forward DNS, FCrDNS match status, daily hosted-domain count (issued.live), owning organization, ASN, country/city, allocation range, last scan time
- [ASN](https://worldip.io/asn/15169): per-ASN page — organization, name, prefix list, country, total IP footprint
- [Organization](https://worldip.io/org/google-llc): per-org page — every ASN and every CIDR range owned, total IP count, country distribution
- [Country](https://worldip.io/country/us): per-country page — top ASNs/orgs, total allocated IPs

## Search

- [Universal search](https://worldip.io/search?q=google): substring match across PTR hostnames, organization names, ASN names
- [PTR-only search](https://worldip.io/search?q=mail&ptr=1): reverse-DNS substring search — find every IP whose PTR contains a token

## Infrastructure

- [Live scanner stats](https://worldip.io/infrastructure): real-time fleet throughput, cycle progress, PTR coverage
- [Network pulse](https://worldip.io/pulse): live BGP and RIR allocation events

## Coverage (measured 2026-08-20)

- 3.69 billion IPv4 addresses — the whole allocated space, rescanned in under 24 hours
- 1.26 billion active PTR (reverse DNS) records resolved
- 79,000+ ASNs indexed
- 250 countries and territories

## Update frequency

- New IP allocations: daily (RIR delegation files + MaxMind)
- Reverse DNS: every routable IPv4 address is rescanned in under 24 hours.
  Each region sweeps its own share continuously, oldest-first; measured
  full-sweep durations are ~16-20 hours per region.
- Forward confirmation (FCrDNS): checked as PTR hostnames are rescanned
- Hosted-domain counts: daily, from issued.live's DNS data
- BGP: live from RIPE RIS collectors

## Related: issued.live

- [issued.live](https://issued.live): WorldIP's sister service for everything in front of an IP — domains, DNS and
  Certificate Transparency certificates. Domain records: https://issued.live/{domain} (also .json and .md).
- Domain data provided by issued.live — for full details visit https://issued.live/pricing

## Citation

Stable URL slugs are safe to link and cite: `/{ip}`, `/asn/{number}`,
`/org/{slug}`, `/country/{cc}`.