Hash Generator (MD5, SHA-256)

What a hash is

A cryptographic hash function turns any input into a fixed-length fingerprint. The same input always gives the same hash, and even a one-character change produces a completely different result. Hashes are used to verify downloads, detect changed files, deduplicate data and build digital signatures.

Verifying a download

Software publishers often list a SHA-256 checksum next to a download. Choose the downloaded file, paste the published checksum into the compare box, and the tool tells you whether it matches. A match means the file arrived intact and unmodified. Files are read on your device and never uploaded, so large installers and private documents are fine.

Which algorithm to use

• SHA-256 is the standard choice today for checksums and integrity checks.
• SHA-384 and SHA-512 give longer digests for higher security margins.
• MD5 and SHA-1 are still common for legacy checksums, but they are broken for security purposes: attackers can create collisions. Don't rely on them for signatures or certificates.

Hashes are not for storing passwords

Plain hashes, even SHA-256, are too fast for password storage. Applications should use a slow, salted algorithm such as Argon2, scrypt or bcrypt. To create strong passwords, use the password generator; to encode binary data as text, see the Base64 encoder.

Hashes in everyday use

Hashes appear in more places than you might expect. Git identifies every commit by a hash of its contents. Backup and sync tools compare hashes to find changed files without comparing every byte. Download sites publish SHA-256 checksums so you can confirm that an installer was not corrupted or tampered with. Websites use Subresource Integrity hashes to make sure a script loaded from a CDN has not been modified. Knowing how to create and compare a hash is a small skill that helps with security and troubleshooting.