Cidr Ipv6

{
  "addressType": "documentation (RFC 3849)",
  "asOf": "2026-10-11T14:45:30.781Z",
  "cidr": "2001:db8:abcd::/48",
  "degraded": false,
  "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
  "expandedFirst": "2001:0db8:abcd:0000:0000:0000:0000:0000",
  "expandedLast": "2001:0db8:abcd:ffff:ffff:ffff:ffff:ffff",
  "first": "2001:db8:abcd::",
  "hostBitsSet": false,
  "last": "2001:db8:abcd:ffff:ffff:ffff:ffff:ffff",
  "matchedSpecialPrefix": "2001:db8::/32",
  "netmask": "ffff:ffff:ffff:0000:0000:0000:0000:0000",
  "network": "2001:db8:abcd::",
  "notChecked": [
    "whether the prefix is allocated or routed (use a registry or routing lookup)",
    "operational norms such as /64 per LAN and /48 per site, which are recommendations (RFC 6177)",
    "…1 more"
  ],
  "prefixLength": 48,
  "reasons": [
    "Network address matches the prefix.",
    "Reverse zone: d.c.b.a.8.b.d.0.1.0.0.2.ip6.arpa."
  ],
  "reverseZone": "d.c.b.a.8.b.d.0.1.0.0.2.ip6.arpa",
  "slash48Count": "1",
  "slash64Count": "65536",
  "source": "RFC 4291 addressing architecture and RFC 5952 text form, computed locally",
  "subnet": {
    "cidr": "2001:db8:abcd:5::/64",
    "first": "2001:db8:abcd:5::",
    "index": "5",
    "last": "2001:db8:abcd:5:ffff:ffff:ffff:ffff",
    "totalSubnets": "65536"
  },
  "summary": "2001:db8:abcd::/48: 1208925819614629174706176 addresses, 65536 /64 networks; documentation (RFC 3849).",
  "totalAddresses": "1208925819614629174706176",
  "totalAddressesPowerOfTwo": 80,
  "verdict": "COMPUTED"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://network-calc.x402tookit.com/cidr-ipv6?cidr=2001%3Adb8%3Aabcd%3A%3A%2F48&index=5&subnetPrefix=64'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://network-calc.x402tookit.com/cidr-ipv6?cidr=2001%3Adb8%3Aabcd%3A%3A%2F48&index=5&subnetPrefix=64' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fnetwork-calc.x402tookit.com%2Fcidr-ipv6
const res = await pay("https://network-calc.x402tookit.com/cidr-ipv6?cidr=2001%3Adb8%3Aabcd%3A%3A%2F48&index=5&subnetPrefix=64");
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://network-calc.x402tookit.com/cidr-ipv6?cidr=2001%3Adb8%3Aabcd%3A%3A%2F48&index=5&subnetPrefix=64")
    print(res.status_code, res.text)