ShadowToolkit

HMAC Generator & Decoder

Generate, decode, and verify HMAC signatures locally in your browser.

100% In-Browser
100% In-Browser PrivacyLocal

Your files and data are processed locally and never leave your device.

Multi-Algorithm HMAC Generator

Computes HMAC-SHA256, HMAC-SHA512, HMAC-SHA384, and HMAC-SHA1 simultaneously.

Format:

What is HMAC Generator & Decoder?

HMAC Generator computes Hash-based Message Authentication Codes (HMAC) using cryptographic secret keys and standard hashing algorithms (SHA-256, SHA-512, SHA-384, MD5). It provides exact cryptographic signatures required for webhook authentication and API security.

Zero-Server Client-Side Guarantee

Unlike legacy online utilities that upload sensitive media and documents to remote cloud storage, Shadow Toolkit executes this entire operation directly within your browser's local runtime. Your raw data never crosses the network.

Key Capabilities

  • Computes HMAC signatures with SHA-256, SHA-512, SHA-384, and MD5 algorithms
  • Uses browser-native Web Cryptography API for cryptographically secure key hashing
  • Hexadecimal and Base64 output format options
  • Built-in signature verification mode to test matching signatures
  • 100% private local execution—your secret API keys never leave your machine

Common Use Cases

1Signing and verifying webhook payloads for Stripe, GitHub, Shopify, and AWS APIs
2Generating authorization headers (AWS Signature v4, REST API request signing)
3Testing message tamper-detection in distributed backend architectures
4Accelerating daily software development workflows, API debugging, and frontend data modeling

How to use HMAC Generator & Decoder

01

Enter Message & Secret Key

Provide the raw message string and your shared secret key.

02

Select Hash Algorithm

Choose HMAC-SHA256, HMAC-SHA512, or HMAC-MD5.

03

Copy HMAC Output

Copy the computed Hex or Base64 signature for your API integration.

04

Integrate with Project

Click 'Copy to Clipboard' or download the file to integrate the verified HMAC Generator & Decoder output directly into your application codebase or API client.

Frequently Asked Questions

A standard hash depends only on the message. An HMAC incorporates a secret cryptographic key, ensuring that only holders of the key can generate or verify the signature.

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