hash7 min
Hash Functions: SHA-2, SHA-3, and HMAC
Understand checksums, cryptographic hashes, HMAC, collision resistance, and why SHA-1 or MD5 should not protect security-sensitive data.
Read more→Hash Generator
Generate SHA-2 (SHA-256, SHA-384, SHA-512) & SHA-3 (SHA3-256, SHA3-384, SHA3-512) hashes + HMAC for free. Compare file & text checksums. 100% client-side.
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Free Online Hash Generator - SHA-256, SHA-512, SHA-3 & HMAC
Our hash generator lets you create cryptographic fingerprints of text and files using the most secure algorithms available. It supports the full SHA-2 family (SHA-256, SHA-384, SHA-512) and SHA-3 (SHA3-256, SHA3-384, SHA3-512), as well as HMAC for secret-key message authentication.
SHA-2 vs SHA-3: Key Differences
SHA-2 is the current widely adopted standard, used in TLS/SSL, digital signatures, blockchain, and X.509 certificates. SHA-3 (Keccak) is the newest NIST standard, released in 2015, with a sponge construction architecture entirely different from SHA-2 Merkle-Damgard construction. This provides complementary resistance: if a weakness were discovered in SHA-2, SHA-3 would not be affected. Both families are secure for current use.
HMAC: Message Authentication
HMAC (Hash-based Message Authentication Code) combines a hash function with a secret key to verify both the integrity and authenticity of a message. It is widely used in APIs, JWT tokens, webhooks, and secure communication protocols.
File Integrity Verification
Hashes let you verify that a file has not been modified by comparing its checksum with the value published by the author. This is essential for software downloads, file transfers, security auditing, and backup verification. All computation happens in your browser using the Web Crypto API, without sending your data to any server.
Frequently Asked Questions
- What hash algorithms does this tool support?
- It supports SHA-1, SHA-256, SHA-384, SHA-512 (SHA-2 family) and SHA3-224, SHA3-256, SHA3-384, SHA3-512 (SHA-3/Keccak family). SHA-2 uses the hardware-accelerated Web Crypto API, while SHA-3 uses the Keccak sponge construction.
- What's the difference between SHA-2 and SHA-3?
- SHA-2 (SHA-256/512) uses the Merkle-Damgard construction. SHA-3 uses the Keccak sponge construction, a fundamentally different design. Both families are secure, but SHA-3 provides cryptographic diversity: if a weakness were found in SHA-2, SHA-3 would remain unaffected.
- Is my data sent to any server?
- No, all hash computation happens locally in your browser. SHA-2 algorithms use the native Web Crypto API and SHA-3 is computed with pure JavaScript. Your data never leaves your device.
- What is HMAC used for?
- HMAC (Hash-based Message Authentication Code) combines a hash with a secret key to verify both the integrity and authenticity of a message. It's used in APIs, JWT, and authentication.
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