Fastly Ip

Check whether an IPv4 or IPv6 address belongs to Fastly's published IP ranges. This is useful when deciding whether an incoming request or DNS result is routed through Fastly.

Install

npm install @tryghost/fastly-ip --save

or

pnpm add @tryghost/fastly-ip

Usage

const isFastlyIp = require('@tryghost/fastly-ip');

if (isFastlyIp('151.101.1.195')) {
    console.log('Request came through Fastly');
}

Develop

This is a monorepo package, managed from the repo root.

Follow the instructions for the top-level repo.

1. git clone this repo & cd into it as usual
2. Run pnpm install to install top-level dependencies.

Run

• pnpm --filter @tryghost/fastly-ip dev

Test

• pnpm --filter @tryghost/fastly-ip lint runs lint
• pnpm --filter @tryghost/fastly-ip test runs lint and tests

Copyright & License

Copyright (c) 2013-2026 Ghost Foundation - Released under the MIT license.