Hash Generator
Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes from any text. Uses the browser's native Web Crypto API.
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.
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.