toolsko

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CORS Response Header Generator

Generate Access-Control headers for Express, Nginx, and Apache.

Tool inputs stay in your browser · optional AI search sends your query

Good to know: Generates cross-origin resource sharing headers to prevent browser CORS request blocking.

How to use it (step by step)

  1. 1Fill in the boxes: “Allowed Origin (e.g. https://example.com or *)”, “Allowed Methods”, “Preflight Cache Duration (seconds)”. Example numbers are already there so you can see how it works; replace them with yours.
  2. 2The result updates instantly as you type (on a phone it is below the boxes).
  3. 3The bold line is the main answer. Tap Copy next to any value to copy it.

Words to know

Nginx / web server
Software that receives visitors and sends them your pages or forwards them to your app.

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