# HMAC generator

> Sign text with an HMAC key that stays local.

[Open tool](https://www.toolcabana.com/da/hmac-generator) · [Udvikling og data](https://www.toolcabana.com/da/category/developer-and-data)

Tool ID: hmac-generator. Requested language: da. Description language: en. Complete guide translation: no; untranslated sections use English.

## Overview (en)

HMAC generator signs a message with a secret key and returns the HMAC using SHA-256, SHA-384 or SHA-512. Both the message and the secret are read as exact UTF-8 bytes. The result can be lowercase hex, uppercase hex or Base64, which helps when checking webhook or API signatures.

## Supported tasks (en)

Sign text with an HMAC key that stays local.

## Steps (en)

1. Paste the source into the input editor, or load the built-in example.
2. Adjust the basic settings, then open Advanced mode for export and fine-tuning options. Custom settings stay active when the panel is closed.
3. Run hmac generator, review the output, then use the available copy or download controls.

## Settings

- Secret key (stays in your browser) (en; key: secret; type: text)
- Algorithm (en; key: algorithm; type: select): SHA-256 [en], SHA-384 [en], SHA-512 [en]
- Digest format (en; key: digestFormat; type: select): hex [en], HEX [en], base64 [en]

## Limitations (en)

Text operations generally accept up to 2,000,000 characters. Individual parsers, generators and formulas apply additional limits shown by their controls.

## Example input

```text
Hello ToolCabana
```

## Privacy and connections (en)

This operation processes its source in your browser. Copy and download are explicit actions; source input is not saved in an account or history.

## Questions (en)

### How do I generate an HMAC SHA-256 signature?

Paste the message, enter the secret key and keep the algorithm set to SHA-256, then run the tool. The output is the keyed HMAC of the message, not a plain hash.

### Is my HMAC secret key encoded as hex or text?

The secret is used as the exact UTF-8 bytes of what you type. A hex or Base64 key string is not decoded first, so enter the key in the form your system uses.

### Can I get the HMAC output in Base64?

Yes. Open Advanced mode and set Digest format to base64. Lowercase hex is the default, and uppercase HEX is also available.

### Where is my input processed?

This operation processes its source in your browser. Copy and download are explicit actions; source input is not saved in an account or history.

### What are the input limits?

Text operations generally accept up to 2,000,000 characters. Individual parsers, generators and formulas apply additional limits shown by their controls.

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