HTTP Header Generator

Build HTTP request headers for standard headers, curl, fetch API, and JSON in one place. All logic runs securely in your browser.

Smart Header Library

Authentication
Content & Negotiation
Caching
Security & Context

⚠ Invalid header name (only letters, numbers, and hyphens allowed)

0 Headers • 0 Characters

Generated Output

Add one or more headers on the left to generate standard, curl, fetch, and JSON output here.

Example HTTP Headers

These example headers show how real-world HTTP requests are typically configured when calling APIs or web services.

Authorization: Bearer YOUR_TOKEN Content-Type: application/json Accept: application/json User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64)
  • Authorization: Sends your access token or credentials so the API can authenticate the request.
  • Content-Type: Tells the server the format of the request body (for example JSON, form data, or XML).
  • Accept: Indicates which response format your client prefers to receive back.
  • User-Agent: Identifies the client (browser, script, or tool) that is making the request.

About HTTP Header Generator

The HTTP Header Generator is an essential tool for developers working with HTTP requests and API development. It allows you to create HTTP headers in the standard format, with a smart library of common headers for quick access. Perfect for API testing, curl and fetch command generation, and understanding HTTP header structure.

Use Cases:

  • Generating headers for API requests
  • Creating curl commands with headers
  • Testing HTTP endpoints with custom headers
  • Understanding HTTP header format
  • Configuring authentication headers
  • Setting content type and accept headers

Key Features:

  • Common headers library for quick access
  • Custom header creation
  • Multiple headers support
  • Standard HTTP header format, curl, fetch API, and JSON outputs
  • Copy headers to clipboard per output format
  • 100% browser-based - no server processing

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Frequently Asked Questions

How do I generate HTTP headers?

Add header name-value pairs using the form. You can add multiple headers by clicking the '+' button. The tool automatically generates the header string in the standard HTTP header format (Name: Value).

Can I use common headers?

Yes! Click on any header from the 'Common Headers' library to quickly add it to your header list. Common headers include Content-Type, Authorization, Accept, User-Agent, and more.

What format are the headers generated in?

Headers are generated in the standard HTTP header format: 'Header-Name: Header Value', one per line. This format is compatible with curl commands, HTTP requests, and API testing tools.

Is the HTTP header generator free to use?

Yes! Our HTTP header generator is 100% free with no registration required, no usage limits, and no hidden fees. You can generate as many HTTP headers as you need for your development work.

Are my headers stored or tracked?

No, all header generation happens locally in your browser. We don't store, save, or have access to any headers you generate. Your privacy is completely protected.

Can I copy the generated headers?

Yes! Click the copy button to copy all generated headers to your clipboard. You can then paste them into curl commands, API testing tools, or your code.

What are common HTTP headers used for?

Common headers include Content-Type (specifies data format), Authorization (authentication tokens), Accept (response format preference), User-Agent (client identification), Cache-Control (caching behavior), and many more for various HTTP operations.

Can I use these headers in curl commands?

Yes! The generated headers are in the standard format compatible with curl. Use the -H flag: curl -H 'Header-Name: Header Value' https://example.com. You can add multiple -H flags for each header.

What's the difference between request and response headers?

Request headers are sent by the client (browser) to the server, while response headers are sent by the server to the client. This tool generates headers that can be used in both contexts, depending on your needs.

Can I add custom headers?

Yes! You can add any custom header name and value. Custom headers often start with 'X-' (e.g., X-API-Key, X-Custom-Header), though this convention is not required in modern HTTP.

How do I use headers in JavaScript fetch API?

Use the headers option: fetch(url, { headers: { 'Header-Name': 'Header Value' } }). For multiple headers, add them as key-value pairs in the headers object. The generated format can be easily converted to this format.