SHA512 Hash Generator

SHA-512 is the 512-bit member of the SHA-2 family of cryptographic hash functions. Given any input it produces a 128-character hexadecimal digest — twice the width of SHA-256, which translates to about 2²⁵⁶ operations to find a collision after the birthday bound. For practical purposes it is indistinguishable from perfectly collision-resistant. Linux /etc/shadow has used SHA-512-based password hashes (with salting and iteration) as the default since 2011. Many high-assurance systems, military and financial, prefer it over SHA-256 where the extra width fits the threat model.

SHA-512 has an unexpected performance advantage on 64-bit CPUs. Its internal state is made of 64-bit words, which match the width of a modern CPU register — so each compression-function round does more work per clock cycle than SHA-256's 32-bit-word rounds. On 64-bit x86, SHA-512 can be 20–40% faster than SHA-256 for bulk data. On 32-bit hardware (old phones, embedded devices) the story reverses — SHA-256 wins.

When to pick SHA-512 over SHA-256. Use SHA-512 when you need defence-in-depth against future quantum advances: Grover's algorithm halves effective security, so SHA-256 drops from ~128 to ~64 bits while SHA-512 stays at 128 bits post-Grover. Use it when you're already embedding the hash in a system that tolerates 64-char field widths (passwords in /etc/shadow, certificates from high-assurance CAs). Use it when you've benchmarked on your actual hardware and it's faster. For most new work, SHA-256 is a fine default — SHA-512 is the right upgrade path when you need more margin.

A common gotcha: SHA-384 is not a shortened SHA-256. SHA-384 is SHA-512 with a different initialisation vector and the output truncated to 384 bits. The full SHA-256 and SHA-512 pipelines are genuinely different internal designs. Do not mix up SHA-384 and SHA-256; they produce different hashes for the same input.

This tool uses the browser's native crypto.subtle.digest("SHA-512"), so it runs at near-native speed. Text is UTF-8 encoded before hashing; files are hashed directly from ArrayBuffer with no server round-trip. The output matches the bytes produced by Linux sha512sum, Python hashlib.sha512, and OpenSSL dgst -sha512.

1. Paste text or pick a file. Any content, up to 500 MB per file.
2. Pick hex or Base64. 128 hex chars or 88 Base64 chars.
3. Copy and verify. Compare against a reference hash to confirm integrity.

• Native Web Crypto SHA-512 — fastest method available in a browser.
• UTF-8-safe text hashing, ArrayBuffer-based file hashing.
• Hex or Base64 output.
• No upload, no logging — hashing happens on your device.