Developer guides
MD5 vs SHA-256: Differences and Which One to Use
Updated 25 September 2026 · 4 min read
A hash function turns any input into a fixed-length fingerprint. Change one letter and the fingerprint changes completely — which makes hashes useful for checking downloads, caching and signatures.
Same input, two hashes
| MD5("hello") | 5d41402abc4b2a76b9719d911017c592 |
| MD5("Hello") | 8b1a9953c4611296a827abf8c47804d7 |
| SHA-256("hello") | 2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824 |
One capital letter changes the MD5 entirely. MD5 is 128 bits (32 hex characters); SHA-256 is 256 bits (64 hex characters).
Generate MD5, SHA-1, SHA-256 and SHA-512 hashesGenerate MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes of any text instantly.The differences that matter
| MD5 | SHA-256 | |
|---|---|---|
| Output | 128-bit | 256-bit |
| Collision resistance | Broken — collisions can be made in seconds | No practical attack known |
| Good for | Non-security checksums, cache keys, deduplication | File integrity, digital signatures, certificates, blockchains |
So which should you use?
- Verifying a download or anything security-related: SHA-256.
- A quick checksum or cache key where nobody is attacking you: MD5 is fine and fast.
- Passwords: neither — use Argon2id, bcrypt or scrypt, which are deliberately slow and salted.
Frequently asked questions
Is MD5 safe to use?
Not for security. Researchers can create two different files with the same MD5 hash, so it can't prove a file or signature is genuine. It's still fine as a quick checksum against accidental corruption.
Should I hash passwords with SHA-256?
No. SHA-256 is too fast, which makes guessing attacks cheap. Use a slow password hash designed for the job — Argon2id, bcrypt or scrypt — with a unique salt per password.