Use the HMAC SHA-512 Generator to create secure hashes for your applications. Ideal for API request signing, token verification, and secure message authentication. Pair it with Base64 Encoder and SHA-512 Generator to strengthen your backend workflows.
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Regular Expression - Documentation
What is HMAC SHA-512?
HMAC (Hash-based Message Authentication Code) is a cryptographic method used to ensure both data integrity and authenticity. It combines:
A secret key
A message
A hashing algorithm (SHA-512 in this case)
SHA-512 is part of the SHA-2 family and generates a 512-bit hash, providing a strong level of security suitable for banking, cryptography, and secure API authentication.
How Does HMAC SHA-512 Work?
The message is combined with a secret key.
This combination is passed through the SHA-512 hashing function.
The result is a fixed-length HMAC hash—secure and tamper-evident.
Unlike regular SHA-512, which just hashes input, HMAC-SHA-512 uses the key to ensure only holders of the key can produce or verify the hash. It resists collision and timing attacks, making it ideal for secure communication.
Practical Examples
Example 1: API Request Signing
Input: "message=Transfer&amount=500"
Secret Key: "myBankSecret123"
HMAC SHA-512 Output:
Use case: Attach this hash to every API request to verify it hasn’t been tampered with.
Example 2: Token Validation
Server generates an HMAC SHA-512 hash of a token using a shared secret.
Client sends the token + hash.
Server recomputes the hash using the same secret to validate authenticity.
Use Cases
API Request Signing: Securely verify each API request from trusted clients.
Webhook Security: Validate that a webhook payload came from the expected source.
JWT Signing (HS512): Use HMAC-SHA512 to sign and verify JWTs in stateless authentication systems.
File or Data Integrity Checks: Ensure downloaded files or transferred data haven’t been modified.
Digital Signature Systems: Provide assurance that a message or document hasn’t changed.
Why Use HMAC SHA-512 Over SHA-512?
Feature | SHA-512 | HMAC SHA-512 |
|---|---|---|
Uses a Secret Key | ❌ No | ✅ Yes |
Used for Encryption | ❌ No | ❌ No (Hash only) |
Ideal for Auth | ❌ Not Recommended | ✅ Strongly Recommended |
Output Size | 128 hex characters | 128 hex characters |
If you’re just hashing a password → SHA-512 might suffice.
If you’re verifying messages or securing API requests → always use HMAC SHA-512.
Pro Tips
Store keys securely – Use environment variables or vaults like AWS Secrets Manager.
Use Base64 – When sending the HMAC hash in headers or URLs, encode it with Base64 Encoder for better compatibility.
Sign JWTs using HS512 – Combine this with our JWT Decoder for full token validation.
Use with API Test Tools – Pair it with SHA-512 Generator for testing data integrity and tampering.
Do not reuse keys across apps – This avoids leaking sensitive validation logic across platforms.
How to Use HMAC SHA-512 Generator
Enter your secret key – This should be known only to trusted parties.
Paste the message – The message could be a query string, token, or file content.
Click generate – The tool outputs a secure 128-character HMAC SHA-512 hash.
Use this hash to sign messages, verify token authenticity, or detect tampering.
