Hashing · 512 bits, 128 hex characters
SHA-512
SHA-512 produces a 512-bit digest and is efficient on 64-bit processors.
Key facts
| Output | 512 bits, 128 hex characters |
|---|---|
| Block size | 1024 bits |
| Rounds | 80 |
| Standard | FIPS 180-4 |
| Variants | SHA-384, SHA-512/256 |
| Performance | Fast on 64-bit CPUs |
A wider digest
SHA-512 uses 64-bit words, so it maps naturally to modern 64-bit processors and can outperform SHA-256 on long inputs. The trade-off is a larger digest and more state to store. For short messages, the difference is negligible.
It is common in password-derived key material (for example, in some wallet standards) and in protocols that want a wide security margin. It is still a fast hash and therefore unsuitable for password storage on its own.
Truncated variants
SHA-384 is a defined truncation with a different initial value, not simply the first 384 bits of SHA-512. SHA-512/256 likewise has its own initialization. Using the named variant matters when interoperating with a standard.
If you only need a checksum and space is tight, a truncated variant is acceptable for integrity. For signatures, follow the protocol's required algorithm.
Frequently asked questions
Is SHA-512 more secure than SHA-256?
Both have no practical collisions. SHA-512 offers a larger digest and different performance characteristics, not a different security category.
Is SHA-384 just truncated SHA-512?
No. It is a distinct variant with different initial values, defined in FIPS 180-4.