CIDR calculator API

Input

Query parameters.

Example request

curl -i 'https://api.lookproof.dev/v1/ip/cidr?cidr=192.0.2.5%2F24'

import asyncio
import os

from eth_account import Account
from x402 import x402Client
from x402.http.clients import x402HttpxClient
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact import register_exact_evm_client


async def main() -> None:
    signer = EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"]))
    client = register_exact_evm_client(x402Client(), signer, networks="eip155:8453")
    async with x402HttpxClient(client) as http:
        response = await http.get('https://api.lookproof.dev/v1/ip/cidr', params={'cidr': '192.0.2.5/24'})
        response.raise_for_status()
        print(response.json())


asyncio.run(main())

import { wrapFetchWithPaymentFromConfig } from "@x402/fetch";
import { ExactEvmScheme } from "@x402/evm";
import { privateKeyToAccount } from "viem/accounts";

const account = privateKeyToAccount(process.env.EVM_PRIVATE_KEY);
const fetchWithPayment = wrapFetchWithPaymentFromConfig(fetch, {
  schemes: [{ network: "eip155:8453", client: new ExactEvmScheme(account) }],
});

const response = await fetchWithPayment("https://api.lookproof.dev/v1/ip/cidr?cidr=192.0.2.5%2F24");
console.log(await response.json());

curl: unpaid request — returns 402 with the price (PAYMENT-REQUIRED). The Python and JavaScript clients pay it and send the request again. Only ordinary wallets (EOA) can pay; smart-contract wallets get a 402 without charge. See payments.

Example response

{
  "checked_at": "2026-10-24T12:00:00Z",
  "data": {
    "first": "192.0.2.0",
    "host_bits_set": true,
    "hostmask": "0.0.0.255",
    "input": "192.0.2.5/24",
    "last": "192.0.2.255",
    "netmask": "255.255.255.0",
    "network": "192.0.2.0/24",
    "prefix": 24,
    "size": "256",
    "version": 4
  },
  "endpoint": "ip.cidr",
  "findings": [
    {
      "code": "IP_HOST_BITS_SET",
      "evidence": {
        "count": 1,
        "items": [
          {
            "input": "192.0.2.5/24",
            "network": "192.0.2.0/24"
          }
        ]
      },
      "explanation": "The address before the slash is not the first address of the network, as in 192.0.2.5/24. The network is 192.0.2.0/24; many configuration files reject the other form or read it as a single host.",
      "message": "The network was given with host bits set.",
      "recommendation": "Write the network with its first address, as shown in the result.",
      "severity": "info"
    }
  ],
  "meta": {
    "cache_hit": false,
    "duration_ms": 42,
    "fresh_until": "2026-10-24T12:05:00Z",
    "observed_at": "2026-10-24T12:00:00Z",
    "resolver": null,
    "source": "offline"
  },
  "request_id": "req_aaaaaaaaaaaaaaaaaaaaaaaaaa",
  "schema_version": "1.0",
  "status": "info"
}

Response fields

Fields in data

Status codes

Errors use the common error body. See errors.

Findings this endpoint can return