letstool/http2registry repository overview

⁠http2registry

Lightweight HTTP gateway that resolves IP addresses and AS numbers against Internet registry allocation data through a JSON REST API.

Send a POST /api/v1/registry request with an IP address or an AS number, get back structured JSON telling you which Regional Internet Registry (ARIN, APNIC, RIPE NCC, LACNIC, AFRINIC) the resource belongs to — along with the matched prefix, country, allocation status and date, and, for AS numbers, the organization and abuse contact.

Two MMDB databases are built automatically from gzipped CSVs served by the letstool CDN and refreshed every 24 hours at 12:30 UTC. No registry account, no manual download, no setup.

The binary embeds a web UI (dark/light mode, 15 languages, RTL support) and an OpenAPI 3.1 spec — no external files, no runtime dependencies.

⁠Quick start

docker run -p 8080:8080 letstool/http2registry:latest

Open http://localhost:8080⁠ to use the web UI, or query the API directly:

# Resolve an IP address to its prefix and Internet registry record
curl -s -X POST http://localhost:8080/api/v1/registry \
  -H "Content-Type: application/json" \
  -d '{"query":"1.1.1.1"}' | jq

# Resolve an AS number to its Internet registry record
curl -s -X POST http://localhost:8080/api/v1/registry \
  -H "Content-Type: application/json" \
  -d '{"query":"AS13335"}' | jq

Example response — IP address lookup:

{
  "status": "SUCCESS",
  "query_type": "ip",
  "query": "1.1.1.1",
  "answer": {
    "ip": "1.1.1.1",
    "prefix": "1.1.1.0/24",
    "size": "256",
    "registry": "apnic",
    "reg_country": "AU",
    "status": "assigned",
    "since": 1313020800,
    "ip_version": 4
  }
}

Example response — AS number lookup:

{
  "status": "SUCCESS",
  "query_type": "asnum",
  "query": "AS13335",
  "answer": {
    "asnum": 13335,
    "registry": "arin",
    "reg_country": "US",
    "status": "assigned",
    "since": 1055721600,
    "abuse_email": "[email protected]",
    "organization": "Cloudflare, Inc.",
    "last_update": 1718740034
  }
}

Query type auto-detection:

• A valid IPv4 or IPv6 address → prefix2reg lookup — returns the matched prefix and its registry, country, status and allocation date
• An AS number in the format AS<n> (case-insensitive: AS13335, as13335) → asn2reg lookup — returns the registry record, including organization and abuse contact

⁠Configuration

CLI flags take priority over environment variables.

Proxy is supported via the standard HTTPS_PROXY, HTTP_PROXY, and NO_PROXY environment variables (same behaviour as curl).

docker run -p 8080:8080 \
  -v ./db:/data:rw \
  -e LISTEN_ADDR=0.0.0.0:8080 \
  letstool/http2registry:latest

⁠Peer sync mode

Set DB_URL to another running http2registry instance to download both MMDB databases directly from its /db/prefix2reg and /db/as2reg endpoints instead of fetching from the CDN. Useful for air-gapped environments or clusters where only one node hits the CDN.

docker run -p 8080:8080 \
  -e DB_URL=http://upstream-host:8080 \
  -v ./db:/data:rw \
  letstool/http2registry:latest

⁠Persistent storage

Mount a volume to /data to cache the databases across container restarts:

docker run -p 8080:8080 \
  -e LISTEN_ADDR=0.0.0.0:8080 \
  -v ./db:/data:rw \
  letstool/http2registry:latest

On restart, if the cached MMDB files are recent enough, they are reloaded immediately without refetching.

⁠Repo

https://github.com/letstool/http2registry⁠

⁠License

This project is licensed under the Apache License, Version 2.0⁠.

Copyright (c) 2026 letstool.net

⁠See also

Internet registry data sourced from the public RIR delegated statistics via the letstool CDN. This project is not affiliated with any RIR or registry data provider. The five Regional Internet Registries — ARIN, APNIC, RIPE NCC, LACNIC and AFRINIC — publish delegated statistics describing IP address and AS number allocations. These files are the canonical public source of the allocation, country, status and date information exposed by this service.