CORS Config Generator

Visual CORS config generator with server templates and header preview for API debugging, security hardening, and release validation

Build CORS response headers and server snippets with presets for quick API debugging and release checks.

CORS Configuration

Preset Templates

Allowed OriginsAllow all origins *

Avoid wildcard origins with credentials; multi-origin templates match the request origin

Allowed Methods

Allowed Request HeadersAllow all request headers *

Exposed Response Headers

Allow credentials

Preflight cache (seconds)

Generated Config

Server / Framework

Generated Config

add_header 'Access-Control-Allow-Origin' '*';
add_header 'Access-Control-Allow-Methods' 'GET, POST, PUT, DELETE, PATCH, OPTIONS';
add_header 'Access-Control-Allow-Headers' '*';


add_header 'Access-Control-Max-Age' '86400';

if ($request_method = 'OPTIONS') {
    return 204;
}

HTTP Response Header Preview

Access-Control-Allow-Origin: *
Access-Control-Allow-Methods: GET, POST, PUT, DELETE, PATCH, OPTIONS
Access-Control-Allow-Headers: *
Access-Control-Max-Age: 86400

About CORS

Simple requests use basic methods and headers
Preflight requests validate complex cross-origin operations
Credentials require explicit origins
Production systems should use allowlists

Documentation

What is the CORS Config Generator

This tool assembles CORS response headers and server templates to standardize cross-origin policies across stacks.

Key Features

Open, restricted, and custom presets to establish a baseline
Server and framework templates with ready-to-use snippets
Live header preview for policy verification
Control methods, request headers, exposed headers, and max age

How to Use

Pick a preset or adjust allowed origins and methods
Choose the server or framework used in your project
Copy the generated snippet and apply it on the server
Verify results against the header preview

Essential Headers

Access-Control-Allow-Origin defines permitted origins
Access-Control-Allow-Methods lists allowed methods
Access-Control-Allow-Headers defines accepted request headers
Access-Control-Expose-Headers lists readable response headers
Access-Control-Allow-Credentials controls credentials
Access-Control-Max-Age sets preflight cache duration

Best Practices

Prefer explicit allowlists in production
Do not combine credentials with wildcard origins
Long max-age values can delay policy changes
Validate with real requests before release