CORS Policy Builder
Visually configure CORS (Cross-Origin Resource Sharing) policies and generate ready-to-use configuration snippets for Express.js, NGINX, AWS API Gateway, Apigee, and Kong.
Quick Start Templates
Choose a pre-configured scenario or build your own custom CORS policy
CORS Configuration Builder
Configure your CORS policy and generate platform-specific code
const cors = require('cors');
const corsOptions = {
origin: 'http://localhost:3000',
methods: ["GET","POST"],
allowedHeaders: ["Content-Type","Authorization"],
credentials: true,
optionsSuccessStatus: 204,
maxAge: 3600
};
app.use(cors(corsOptions));
CORS Documentation & Best Practices
Comprehensive guide to understanding and implementing secure CORS policies
What is CORS (Cross-Origin Resource Sharing)?
CORS is a security mechanism implemented by web browsers that controls how web pages in one domain can access resources from another domain. It prevents unauthorized cross-origin requests while allowing legitimate ones.
- Prevents unauthorized cross-domain requests
- Enables secure API consumption from web apps
- Uses HTTP headers to communicate policies
Key CORS Headers
Access-Control-Allow-Origin
- Allowed originsAccess-Control-Allow-Methods
- Allowed HTTP methodsAccess-Control-Allow-Headers
- Allowed request headers
Important Security Warning
CORS misconfigurations can expose your application to security vulnerabilities. Always validate your CORS policies in a staging environment before deploying to production. Never use wildcard origins (*) with credentials enabled, as this creates serious security risks.