Hash Generator

A cryptographic hash function takes any input text and produces a fixed-length string of hex characters — the digest — such that even a one-character change in the input produces a completely different digest. This tool runs your text through the browser's native Web Crypto API to compute SHA-1, SHA-256, SHA-384, and SHA-512 digests side by side, entirely on-device, with nothing sent over the network.

Hashing is one-way and deterministic, not encryption: there's no key involved, and there's no way to recover the original text from the digest, unlike encryption which is designed to be reversed with the right key. SHA-1 is included for compatibility with older systems but is considered cryptographically weak — collisions have been demonstrated in practice — so SHA-256 or a longer variant is the safer default for anything security-sensitive. MD5 isn't offered here at all: it's not exposed by the Web Crypto API and is broken badly enough that it shouldn't be used for integrity checks anymore.

Common uses include verifying a downloaded file matches its published checksum, generating a stable fingerprint for caching or deduplication, or comparing two pieces of text for exact equality without storing the text itself — hashes of passwords for real authentication systems should use a dedicated password-hashing algorithm (like bcrypt or Argon2) rather than a raw SHA hash.

A hash function maps input of any size to a fixed-length digest. It is deterministic and one-way, and a tiny input change produces an unrelated output. SHA-256 gives 256 bits, shown as 64 hex characters.

SHA-1 is broken for collision resistance and should not be used for security. SHA-256 and above are fine for checksums and integrity. For storing passwords, use a slow, salted algorithm such as bcrypt, scrypt or Argon2 rather than a plain SHA hash. Digests are computed by the browser's Web Crypto API on your device.