@pfeiferio/ipv4

@pfeiferio/ipv4

Strict and well-tested IPv4 address and network utilities for Node.js.

• ESM only
• Node.js ≥ 18
• TypeScript-first
• No dependencies
• Full test coverage

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Installation

npm install @pfeiferio/ipv4

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Basic Usage

import { ipV4 } from '@pfeiferio/ipv4'

const ip = ipV4('192.168.1.10/24')

ip.address            // "192.168.1.10"
ip.prefix             // 24
ip.addressWithCidr    // "192.168.1.10/24"
ip.toInteger()        // 3232235786

Default prefix is /32.

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IPv4Address examples

Create addresses

ipV4('1.1.1.1')
ipV4('1.1.1.1/32')
ipV4(3232235777)

Prefix handling (immutable)

const ip = ipV4('10.0.0.1')
const withPrefix = ip.withPrefix(16)

ip.addressWithCidr        // "10.0.0.1/32"
withPrefix.addressWithCidr // "10.0.0.1/16"

Address comparison

ip.equals(ipV4('10.0.0.1/32'))        // true
ip.isSameAddress(ipV4('10.0.0.1/8'))  // true

Navigation

ipV4('1.1.1.1').next().address   // "1.1.1.2"
ipV4('1.1.1.1').prev().address   // "1.1.1.0"

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IPv4Network examples

Create networks

const net = ipV4('192.168.1.10/24').network()

net.addressWithCidr   // "192.168.1.0/24"
net.size              // 256
net.hostCount         // 254

Network helpers

net.firstHost.address   // "192.168.1.1"
net.lastHost.address    // "192.168.1.254"
net.broadcast.address   // "192.168.1.255"

Containment & relations

net.contains('192.168.1.42')                 // true
net.overlaps('192.168.1.128/25')             // true
net.containsNetwork('192.168.1.128/25')      // true
net.isSubnetOf('192.168.0.0/16')              // true
net.isSupernetOf('192.168.1.128/25')          // true

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Iteration

Usable hosts

for (const host of net.hosts()) {
  console.log(host.address)
}

All addresses

for (const addr of net.addresses()) {
  console.log(addr.address)
}

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Utilities

import { ipToInt, intToIp } from '@pfeiferio/ipv4'

ipToInt('192.168.1.1')   // 3232235777
intToIp(3232235777)      // "192.168.1.1"

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Design notes

• Prefix defaults to /32
• Network addresses are always normalized
• No implicit magic
• /0, /31, /32 handled correctly

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License

MIT