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HTTP Header Builder

HTTP Header Builder

Assemble request headers and export them as a raw request, curl, or fetch — in your browser

Request

Method, URL, and headers

About this tool

Assemble HTTP request headers from a form and export them as a raw request block, a curl command, or a JavaScript fetch() call HTTP Header Builder runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.

What this tool does not do

  • HTTP Header Builder is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.

How do I use this tool?

  1. How do I use HTTP Header Builder?

    Open HTTP Header Builder, enter or paste your input, and copy the result. The page works without an account.

Related guides

HTTP Request Headers Every Developer Should Know

A tour of the request headers you'll actually use — Authorization, Content-Type, Accept, and friends — with how to build them for curl, fetch, and raw requests.

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