100% local and secure
Your data stays on your device and is never sent to our servers.
HTTP Header Builder
Prepare a set of HTTP headers, define their values, and retrieve the result in a syntax ready for network requests.
- 100% local
- Instant
- Free
- No account
- Works offline
- Clipboard
Quick preset
One header per line: Name: value
Data not sent
HTTP format
JSON format
Fetch format
Why use this tool?
Prepare consistent HTTP headers and export them as raw HTTP, JSON, or Fetch syntax.
Smart processing
Generate, convert, or validate technical data with purpose-built controls.
Supported formats
Technical formats and syntaxes suited to each generator, converter, or validator.
Save time
Get a clean, ready-to-use result in seconds without installing software or configuring a complex workflow.
Fonctionnement
How does this tool work?
The tool reads each name-value pair, normalizes header names, and replaces duplicates case-insensitively. It then generates three consistent representations that can be reused in requests, configuration files, or JavaScript code.
Use cases
Prepare a JSON API
Create Accept and Content-Type headers for a REST API.
Configure caching
Assemble Cache-Control directives for a selected environment.
Build a CORS setup
Produce a consistent group of CORS response headers.
Guide
How to use this tool
- 1
Enter the data
Fill in the fields or paste the information required for the operation.
- 2
Configure the process
Choose the options, formats, or algorithms that fit your use case.
- 3
Use the result
Generate and copy the locally produced report, code, or value.
Tips and best practices
- Avoid entering production secrets on a shared device.
- Always review generated output before using it in a real environment.
- All operations are performed locally in your browser.
Frequently asked questions
Are data sent to a server?
No. Processing runs locally in your browser and the entered information is not transmitted.
Can generated results be copied?
Yes. Every generated output can be copied directly for reuse in code or documentation.
Can I use sensitive data?
Processing is local, but production secrets should still be avoided on shared or untrusted devices.
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