Getting Started with Cloudflare Workers

Cloudflare Workers let you run JavaScript (or TypeScript, Rust via WASM, and more) at the edge — inside Cloudflare’s global network, close to your users. There’s no server to manage, no cold-start penalty, and your code runs in ~300 locations worldwide by default.

This guide walks through everything you need to ship your first Worker.

Prerequisites

• A free Cloudflare account
• Node.js 18+ installed locally

1. Install Wrangler

Wrangler is the official Cloudflare CLI. It handles local development, deployment, secret management, and more.

npm install -g wrangler
wrangler login

The wrangler login command opens a browser window to authenticate with your Cloudflare account.

2. Create a new Worker project

npm create cloudflare@latest my-worker
cd my-worker

You’ll be prompted to choose a template. Pick “Hello World” Worker to start simple.

This creates a project with:

my-worker/
├── src/
│   └── index.ts       ← your Worker code
├── wrangler.jsonc     ← project config
└── package.json

3. Write your first Worker

Open src/index.ts. The default looks like this:

export default {
  async fetch(request: Request): Promise<Response> {
    return new Response('Hello, World!');
  },
};

Every Worker exports a default object with a fetch handler. It receives a standard Request and must return a Response. That’s it — no framework required.

Let’s make it slightly more interesting:

export default {
  async fetch(request: Request): Promise<Response> {
    const url = new URL(request.url);
    const name = url.searchParams.get('name') ?? 'World';

    return new Response(`Hello, ${name}!`, {
      headers: { 'content-type': 'text/plain' },
    });
  },
};

4. Run it locally

npm run dev

Wrangler starts a local dev server at http://localhost:8787. Try:

curl "http://localhost:8787?name=Cloudflare"
# → Hello, Cloudflare!

Local dev uses Miniflare under the hood — a full Workers runtime simulator that supports KV, Durable Objects, R2, and most other bindings.

5. Deploy

npm run deploy

That’s it. Wrangler builds your Worker, uploads it to Cloudflare, and gives you a URL like https://my-worker.your-subdomain.workers.dev.

Your Worker is now running in 300+ cities worldwide. Every request is handled by the location closest to the user.

What’s next?

• Add KV storage — persist key-value data globally
• Use D1 — SQLite at the edge
• Schedule with Cron Triggers — run Workers on a schedule
• Explore the full Workers API — the official docs

Workers have a generous free tier: 100,000 requests/day, with no cold starts, ever.