Hashing vs. Encryption: What's the Difference?

Hashing is a one-way transformation used for verification; encryption is reversible and used to keep data confidential.

Two fundamentally different goals

Encryption exists to keep data confidential while still allowing it to be recovered later by someone with the right key. Hashing exists to produce a fixed-size fingerprint of data that can be used to verify integrity or compare values — with no intention or ability to recover the original input from the hash.

Why hashes can't be "decrypted"

A hash function is deliberately one-way and lossy: many different inputs can theoretically map to outputs of the same fixed length, and the function is designed so there's no efficient way to reverse it. There is no secret key that "un-hashes" a value, because hashing was never a reversible operation to begin with — describing it as "encrypted" or asking to "decrypt" a hash is a common but fundamental misunderstanding.

Common uses for each

Encryption is used for protecting data in transit (HTTPS) and at rest (encrypted databases or files) where the legitimate recipient needs to recover the original content. Hashing is used for verifying file integrity (comparing checksums), detecting whether data changed, and as one ingredient in secure password storage systems.

A note on password storage

Storing passwords doesn't use a single raw hash like SHA-256 directly — real systems use purpose-built, deliberately slow password-hashing algorithms (bcrypt, scrypt, Argon2) combined with a per-user random salt, specifically to resist large-scale guessing attacks in a way a fast general-purpose hash function like SHA-256 was never designed to do.