SHA-512/256 generator

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Processed instantly and never stored — we keep no copy of your input.

What Is SHA-512/256?

SHA-512/256 runs the SHA-512 algorithm but outputs only 256 bits, using unique initial values that make it a separate function from both SHA-256 and truncated SHA-512. It is the modern answer to "I want 256-bit security with 64-bit speed."

Why It Exists

On 64-bit CPUs, the SHA-512 core is significantly faster than SHA-256's 32-bit core — so SHA-512/256 gives you SHA-256-sized digests at SHA-512 speed, with proper domain separation thrown in. Several newer protocols chose it for exactly this reason.

Not Interchangeable

A SHA-512/256 digest of "hello" differs completely from its SHA-256 digest. Always match the exact algorithm your protocol specifies.

How to Use the SHA-512/256 Hash Generator

SHA-512/256 runs the SHA-512 algorithm with distinct initial values and truncates the output to 256 bits — it is a separate standardised function, not a chopped-down SHA-512 digest.

Paste the message for SHA-512/256 — truncated SHA-512 with 256-bit output and its own initial values.
Click the hash button to compute the 256-bit digest with SHA-512/256 initial values.
Copy the 64-character hexadecimal result; it will differ from both SHA-256 and plain truncated SHA-512.

Example

Hashing the word hello with SHA-512/256 always produces e30d87cfa2a75db545eac4d61baf970366a8357c7f72fa95b52d0accb698f13a. Compare this with the SHA-256 hash of the same word — both are 64 characters, but the values are entirely different.

Frequently Asked Questions

Why not just truncate a SHA-512 digest myself?
Because SHA-512/256 uses different initial values, its output is a fully standardised, independent function. Plain truncation of SHA-512 can also leak length-extension properties that SHA-512/256 avoids.

Where is SHA-512/256 used?
It is a FIPS 180-4 standard used in OpenBSD, DNSSEC tooling and systems that want 64-bit-platform performance with a 256-bit digest size.

Does it run faster than SHA-256?
On 64-bit processors, yes — the underlying SHA-512 compression function processes data in larger blocks, which is exactly why this variant was created.