CORS Policy Generator
Generate secure cross-origin resource sharing headers with our free CORS policy generator. Configure origins, methods, and headers instantly on Doffl.
About CORS Policy Generator
The CORS Policy Generator helps developers create accurate Cross-Origin Resource Sharing (CORS) headers for web servers and APIs. By selecting allowed origins, HTTP methods, headers, and credential policies, you can generate ready-to-use configurations that prevent browser cross-origin blocking while maintaining tight security.
Built directly into your browser, this tool processes everything client-side without sending your domain or configuration parameters to external servers. It is ideal for backend engineers, API designers, and DevOps professionals looking to quickly configure Nginx, Apache, Express, or raw HTTP headers.
Key features
- Generates Access-Control HTTP headers instantly
- Supports custom allowed origins, methods, and headers
- Configures preflight cache duration with Max-Age
- Enables credential sharing toggles for cookies and auth
- Outputs snippets for Nginx, Apache, and Express
- Runs completely in the browser for privacy
How to use CORS Policy Generator
- Specify your allowed origin domains or wildcards.
- Select permitted HTTP request methods like GET, POST, or PUT.
- Choose allowed and exposed custom request headers.
- Configure credential support and preflight max-age caching duration.
- Copy the generated HTTP headers or server configuration snippet.
Who is it for?
- API developers resolving cross-origin request errors on frontend applications
- DevOps engineers configuring reverse proxy headers in Nginx or Apache
- Frontend teams prototyping integrations with third-party microservices
- Security teams establishing strict cross-origin policies for production endpoints
Frequently asked questions
What is a CORS policy?
A CORS (Cross-Origin Resource Sharing) policy is a set of HTTP headers that tells a web browser whether a web application running at one origin can request resources from a server at a different origin.
What does the Access-Control-Allow-Origin header do?
It specifies which origin or origins are allowed to access server resources. Setting it to a wildcard allows any origin, while specifying an exact domain restricts access to that domain.
Why should I avoid using a wildcard origin with credentials?
Browsers reject cross-origin requests that use both a wildcard origin and credentials like cookies or authorization headers. You must specify an explicit origin when Access-Control-Allow-Credentials is set to true.
What is a CORS preflight request?
A preflight request is an automated HTTP OPTIONS request sent by the browser before the primary request. It checks whether the server permits the requested HTTP method and custom headers.
Is this CORS policy generator free to use?
Yes, this tool is completely free with no registration or software installation required.