corsx

corsx is a lightweight CORS proxy running on Cloudflare's edge network. Helps client-side JavaScript fetch content from any URL without CORS restrictions.

Live Demo

https://corsx.kezanwar.workers.dev

Usage

const proxyUrl = "https://corsx.kezanwar.workers.dev/proxy";
const targetUrl = "https://api.example.com/data";

const response = await fetch(
  `${proxyUrl}?url=${encodeURIComponent(targetUrl)}`,
);
const data = await response.json();

Deploy Your Own

1. Install Wrangler CLI:

npm install -g wrangler

2. Login to Cloudflare:

wrangler login

3. Clone and deploy:

git clone https://github.com/kezanwar/corsx
cd corsx

4. Create the rate limit KV namespace:

npx wrangler kv namespace create RATE_LIMIT

5. Copy the ID from the output and update wrangler.toml:

[[kv_namespaces]]
binding = "RATE_LIMIT"
id = "your-id-here"

6. Deploy:

wrangler deploy

That's it. You'll get a URL like https://corsx.YOUR_SUBDOMAIN.workers.dev.

Endpoints

Endpoint	Description
GET /	Landing page with docs and interactive demo
GET /proxy?url=<url>	Proxy a request
POST /proxy?url=<url>	Proxy a POST request (body forwarded)
GET /health	Health check

Features

• Fast — Runs on Cloudflare's global edge network
• Free — 100k requests/day on free tier
• SSRF Protection — Blocks internal/private IPs
• Full CORS — All the right headers, preflight handled
• POST Support — Forwards request body

Response Headers

Added to all proxied responses:

Access-Control-Allow-Origin: *
Access-Control-Allow-Methods: GET, POST, OPTIONS
X-Proxied-By: corsx
X-Original-URL: <original-url>

Local Development

wrangler dev

Opens a local server at http://localhost:8787.

Custom Domain

Edit wrangler.toml:

routes = [
  { pattern = "cors.yourdomain.com", custom_domain = true }
]

Then redeploy with wrangler deploy.

License

MIT