Free SHA-256 Hash Generator
This hash tool computes SHA-256 (plus SHA-1 and SHA-512) digests of any text using the browser's Web Crypto API, the same primitives security software uses. It is designed for verifying downloads against published checksums and generating deterministic fingerprints. Nothing is uploaded.
How it works
Text is UTF-8 encoded and digested in one pass; bytes render as lowercase hex. SHA-256 outputs 64 hex characters, SHA-512 outputs 128, SHA-1 outputs 40. Identical input always yields identical output, while any one-character change avalanches roughly half the bits.
Example
| Input | SHA-256 (first 16) |
|---|---|
hello | 2cf24dba5fb0a30e… |
Frequently asked questions
What is a hash used for?
Integrity checks: compare a download's hash against the publisher's checksum to confirm it arrived intact.
SHA-256 vs SHA-512?
Both are secure. SHA-512 digests faster on 64-bit servers but produces longer output; either suits checksums.
Why is SHA-1 marked legacy?
Collision attacks make it unsuitable for security. Fine for non-security fingerprints, never for signatures.
Can a hash be reversed?
No. Hashes are one-way; recovering input requires brute force, infeasible for strong inputs.
Is my text uploaded?
No. Hashing happens locally via Web Crypto.
Related tools
- Password Generator , secrets done right.
- Base64 Encoder , reversible encoding contrast.
- UUID Generator , random identifiers.
- Guide: Small Business Digital Toolkit