What can I create with the header builder?

Build HTTP request or response header lines by choosing a header name and entering its value, then copy the resulting configuration.

Does it validate header values?

It helps format common headers, but always check the relevant HTTP specification and your server's requirements for strict validation.

Can I use the output in server configuration?

Yes, as a reference. Adapt the generated lines to your server, proxy, curl command, or application framework's syntax.

HTTP Header Builder

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

Request

Method, URL, and headers

Headers

Output

Copy in your preferred format

GET /v1/users HTTP/1.1
Host: api.example.com
Accept: application/json
Authorization: Bearer <token>

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.

API Mock Server

Define mock REST routes and intercept fetch calls client-side

Bandwidth Calculator

Estimate how long a file takes to transfer at a given connection speed — correctly handling bits vs bytes (Mbps vs MB/s) and SI vs binary size units

Broken Link Checker

Extract http(s) links from pasted HTML and check them via proxy

cURL to Code Converter

Convert cURL commands to code snippets in multiple languages. Parse cURL and generate JavaScript, Python, PHP, and more.

DNS Lookup Tool

Query DNS records and resolve domain names to IP addresses

DNS Propagation Checker

Compare DNS answers from global public resolvers and see propagation consensus instantly