SHA Hash Generator — SHA-256 in Your Browser
Hash text with SHA-1, SHA-256, SHA-384, or SHA-512 using Web Crypto. Nothing is uploaded. MD5 is not offered.
About Hash Functions
A cryptographic hash function maps input of any size to a fixed-size digest. It is deterministic (same input → same output), fast to compute, and practically impossible to reverse. This tool uses the browser's SubtleCrypto.digest() API — no data ever leaves your device.
Even a single character change completely changes the output — this is the avalanche effect. Read more: Hash Algorithms Guide: MD5, SHA-1, SHA-256 and Beyond.
Algorithm Comparison
- SHA-1 — 160-bit. Deprecated for security, still used in Git
- SHA-256 — 256-bit. Recommended for most uses
- SHA-384 — 384-bit. Higher security margin
- SHA-512 — 512-bit. Maximum security, larger output
Common Use Cases
- File integrity — verify a download is unmodified
- Password storage — store salted hashes, not plaintext
- Digital signatures — sign the hash, not the full document
- Checksums — detect accidental data corruption
- Need a random secret to hash? Use the Random String Generator
Frequently Asked Questions
Can I reverse a hash?
No — hash functions are one-way. You cannot reverse a hash to get the original input. Attackers use rainbow tables (precomputed hash databases) against weak or unsalted hashes.
Should I use SHA-1?
Not for security-sensitive applications. SHA-1 collision attacks have been demonstrated. Use SHA-256 or higher for new projects.
Why not MD5?
MD5 is not available in the browser's Web Crypto API because it is cryptographically broken. For legacy MD5 support, use a dedicated JS library.
Does this hash generator upload my text?
No. Hashing uses SubtleCrypto.digest in your browser. The input never leaves the device.
How to hash passwords safely?
Don't use raw SHA hashes for passwords. Use bcrypt, scrypt, or Argon2 — these are slow by design, making brute-force attacks expensive.