Privacy & Tech

How do encryption and hashing differ in data protection?

Encryption protects readable information by transforming it into ciphertext that can be decrypted with the appropriate key. Cryptographic hashing produces a digest designed to make recovering the original input computationally impractical.

Aspect	Encryption	Cryptographic hashing
Main purpose	Protect confidentiality.	Support integrity checks and other verification tasks.
Recovering the input	Intended to be possible with the correct key.	No decryption operation is provided.
Typical website use	Protecting information sent over HTTPS.	Checking whether a downloaded file matches an expected digest.
Main consideration	Secure algorithms, implementation and key management.	Suitable algorithms and protection against guessing predictable inputs.

A website may use both technologies because they address different needs. Neither establishes that collecting the underlying information was appropriate.

Microsoft’s explanation of hashing and encryption describes their different functions. The same distinction matters when assessing whether hashed email addresses are anonymous: a one-way transformation does not rule out matching or guessing.