Free CORS Header Configuration Generator Online
Generate Access-Control-Allow-Origin, Methods, and Headers for Express, Next.js, Nginx, and AWS API Gateway to resolve CORS errors. — 100% free online utility, zero sign-up, zero paywalls, and private client-side processing.
How It Works
Enter Allowed Origins
Specify allowed domains (e.g., https://example.com) or wildcard (*).
Choose Allowed Methods
Select GET, POST, PUT, DELETE, OPTIONS, PATCH.
Copy Config
Get drop-in middleware code for Express, Fastify, or Nginx.
Frequently Asked Questions
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