# @fastify/proxy-addr > Determine the address of a proxied request Latest version **5.1.1** (published 2026-09-15) · MIT license · 0 weekly downloads ## Install ```sh npm install @fastify/proxy-addr pnpm add @fastify/proxy-addr yarn add @fastify/proxy-addr bun add @fastify/proxy-addr ``` ## Health **Score 65/100 (B)** — status: active. Positive: has types; no vulnerabilities; recently updated; high maintenance score; high quality score. Warnings: low downloads; no esm support. ## Facts | | | |---|---| | Version | 5.1.1 | | Published | 2026-09-15 | | First published | 2021-02-12 | | Weekly downloads | 0 | | License | MIT | | TypeScript types | bundled | | Module format | CommonJS | | Dependencies | 2 | | Unpacked size | 40.8 KB | | Known vulnerabilities | 0 | | Install scripts | no | | GitHub stars | 7 | | Author | Douglas Christopher Wilson | | Maintainers | matteo.collina, jsumners, eomm, climba03003, gurgunday, fdawgs, ivan-tymoshenko | | Keywords | ip, proxy, x-forwarded-for | ## Links - npm: https://www.npmjs.com/package/@fastify/proxy-addr - Repository: https://github.com/fastify/proxy-addr - Homepage: https://github.com/fastify/proxy-addr#readme - Issues: https://github.com/fastify/proxy-addr/issues - Funding: https://github.com/sponsors/fastify - npm.io page: https://npm.io/package/@fastify/proxy-addr ## Dependencies (2) - [ipaddr.js](https://npm.io/package/ipaddr.js.md) ^2.1.0 - [@fastify/forwarded](https://npm.io/package/@fastify/forwarded.md) ^3.0.0 ## Alternatives - [lodash.startswith](https://npm.io/package/lodash.startswith.md) — 769.7K weekly downloads - [@tarojs/service](https://npm.io/package/@tarojs/service.md) — 33.9K weekly downloads - [io.extendreality.tilia.indicators.spatialtargets.unity](https://npm.io/package/io.extendreality.tilia.indicators.spatialtargets.unity.md) — 131 weekly downloads - [@rtarojs/taro](https://npm.io/package/@rtarojs/taro.md) — 90 weekly downloads - [node-branch-io](https://npm.io/package/node-branch-io.md) — 50 weekly downloads ## Recent versions - 5.1.1 (latest) — 2026-09-15 - 5.0.0 (next) — 2024-09-04 - 5.1.0 — 2025-09-28 - 5.0.0-pre.fv5.1 — 2024-06-19 - 4.1.0 — 2022-12-15 - 4.0.0 — 2022-05-25 - 3.0.0 — 2021-02-12 ## README # proxy-addr [![CI](https://github.com/fastify/proxy-addr/actions/workflows/ci.yml/badge.svg?branch=main)](https://github.com/fastify/proxy-addr/actions/workflows/ci.yml) [![NPM version](https://img.shields.io/npm/v/@fastify/proxy-addr.svg?style=flat)](https://www.npmjs.com/package/@fastify/proxy-addr) [![neostandard javascript style](https://img.shields.io/badge/code_style-neostandard-brightgreen?style=flat)](https://github.com/neostandard/neostandard) Determine the address of a proxied request. Forked from https://github.com/jshttp/proxy-addr to address https://github.com/jshttp/forwarded/pull/9. ## Install ```sh $ npm i @fastify/proxy-addr ``` ## API ```js const proxyaddr = require('@fastify/proxy-addr') ``` ### proxyaddr(req, trust) Return the address of the request, using the given `trust` parameter. The `trust` argument is a function that returns `true` if you trust the address, `false` if you don't. The closest untrusted address is returned. ```js proxyaddr(req, function (addr) { return addr === '127.0.0.1' }) proxyaddr(req, function (addr, i) { return i < 1 }) ``` The `trust` argument may also be a single IP address string or an array of trusted addresses, as plain IP addresses, CIDR-formatted strings, or IP/netmask strings. ```js proxyaddr(req, '127.0.0.1') proxyaddr(req, ['127.0.0.0/8', '10.0.0.0/8']) proxyaddr(req, ['127.0.0.0/255.0.0.0', '192.168.0.0/255.255.0.0']) ``` This module also supports IPv6. Your IPv6 addresses will be normalized automatically (i.e. `fe80::00ed:1` equals `fe80:0:0:0:0:0:ed:1`). ```js proxyaddr(req, '::1') proxyaddr(req, ['::1/128', 'fe80::/10']) ``` This module will automatically work with IPv4-mapped IPv6 addresses as well to support node.js in IPv6-only mode. This means that you do not have to specify both `::ffff:a00:1` and `10.0.0.1`. As a convenience, this module also takes certain pre-defined names in addition to IP addresses, which expand into IP addresses: ```js proxyaddr(req, 'loopback') proxyaddr(req, ['loopback', 'fc00:ac:1ab5:fff::1/64']) ``` * `loopback`: IPv4 and IPv6 loopback addresses (like `::1` and `127.0.0.1`). * `linklocal`: IPv4 and IPv6 link-local addresses (like `fe80::1:1:1:1` and `169.254.0.1`). * `uniquelocal`: IPv4 private addresses and IPv6 unique-local addresses (like `fc00:ac:1ab5:fff::1` and `192.168.0.1`). When `trust` is specified as a function, it will be called for each address to determine if it is a trusted address. The function is given two arguments: `addr` and `i`, where `addr` is a string of the address to check and `i` is a number that represents the distance from the socket address. ### proxyaddr.all(req, [trust]) Return all the request addresses, optionally stopping at the first untrusted. This array is ordered from closest to furthest (i.e. `arr[0] === req.connection.remoteAddress`). ```js proxyaddr.all(req) ``` The optional `trust` argument takes the same arguments as `trust` does in `proxyaddr(req, trust)`. ```js proxyaddr.all(req, 'loopback') ``` ### proxyaddr.compile(val) Compiles argument `val` into a `trust` function. This function takes the same arguments as `trust` does in `proxyaddr(req, trust)` and returns a function suitable for `proxyaddr(req, trust)`. ```js const trust = proxyaddr.compile('loopback') const addr = proxyaddr(req, trust) ``` This function is meant to be optimized for use against every request. It is recommended that a trust function be compiled up-front for the trusted configuration and passed to proxyaddr(req, trust) for each request. ## Testing ```sh $ npm test ``` ## Benchmarks ```sh $ npm run bench ``` ## License Licensed under [MIT](./LICENSE). --- _Source: https://npm.io/package/@fastify/proxy-addr · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._