SHA-512 Hash Generator
A 512-bit digest, 128 hex characters, computed in this tab.
What makes SHA-512 different from SHA-256
Both belong to SHA-2 and share a Merkle–Damgård construction, but SHA-512 operates on 64-bit words with 80 rounds and a 1024-bit block, while SHA-256 uses 32-bit words with 64 rounds and a 512-bit block. They have different initial hash values and different round constants, so the two never produce related output. abc hashes to ddaf35a193617aba...3d0880d2, 128 hex characters.
The counter-intuitive performance fact
On 64-bit hardware, SHA-512 frequently runs faster than SHA-256 in native implementations, because each instruction processes twice as many bits. In this page's pure-JavaScript implementation the arithmetic is emulated, so SHA-256 is usually the quicker of the two; in OpenSSL, openssl speed sha256 sha512 often shows SHA-512 ahead on large inputs.
The truncated family
- SHA-384 — SHA-512 with a different initial value, truncated to 384 bits. Used in TLS cipher suites and by some HSMs.
- SHA-512/256 and SHA-512/224 — FIPS 180-4 truncations with their own IVs; SHA-512/256 resists length-extension attacks that plain SHA-256 inherits.
- SHA-512 full — used by checksum manifests, some package managers, and archive formats.
Longer digest is not automatically safer here
512 bits of output gives no meaningful security advantage over 256 bits for collision resistance in practice; both are far beyond reach. Choose SHA-512 when a downstream system specifies it, not because you want extra padding of safety.
How to use it
- Paste or type your text.
- Leave the selector on SHA-512.
- Copy the 128 hex characters.
Worth knowing
- Digest length: 512 bits / 128 hex characters.
- 64-bit words, 80 rounds, 1024-bit block — FIPS 180-4.
- Truncated forms with distinct IVs: SHA-384, SHA-512/256, SHA-512/224.
- Length-extension applies to SHA-256-class hashes; use HMAC when a secret is involved.
Limitations
- Not a password hash — it is fast, and speed is the enemy when cracking cost matters.
- In pure JavaScript the 64-bit emulation is slower than native SHA-512.
- Output length is unwieldy for URLs and cache keys; prefer a shorter digest there.
- A digest proves identical bytes, not trustworthy content.