About these hash algorithms
A hash function turns input of any size into a fixed-length fingerprint. The same input always produces the same hash, and changing even one character produces a completely different one — useful for verifying file integrity, detecting duplicates, or generating deterministic identifiers.
- SHA-256 / SHA-512 — modern, cryptographically secure. Use these for anything security-sensitive (password hashing should still use a dedicated algorithm like bcrypt or Argon2, not a raw hash).
- SHA-1 — cryptographically broken for collision resistance since 2017, but still common for non-security checksums (e.g. Git object IDs).
- MD5 — cryptographically broken and fast to brute-force. Included here only for legacy compatibility (e.g. checking a vendor-supplied MD5 checksum) — never use it for anything security-sensitive.
How this is computed
SHA-1/256/512 use the browser's native Web Crypto API (crypto.subtle.digest). MD5 isn't implemented by Web Crypto (browsers deliberately omit insecure algorithms), so this tool includes a small pure-JavaScript MD5 implementation instead. Either way, your text is hashed locally and never leaves your browser.