MD5 vs SHA-256
Differences, use cases, and when to use each
MD5 produces 128-bit hashes but has known collision vulnerabilities. SHA-256 produces 256-bit hashes and remains cryptographically secure. MD5 is faster but broken for security; SHA-256 is the current standard.
Quick Comparison
| Feature | MD5 | SHA-256 |
|---|---|---|
| Hash Size | 128-bit (32 hex chars) | 256-bit (64 hex chars) |
| Security | Broken (collisions found) | Secure (no known attacks) |
| Speed | Very fast | Slower than MD5 |
| Collision Resistance | No (practical attacks exist) | Yes |
| Recommended Use | Checksums only (non-security) | All purposes |
When to Use Each
When to Use MD5
Use MD5 only for non-security checksums — file deduplication, cache keys, and data integrity checks where attacks aren't a concern.
When to Use SHA-256
Use SHA-256 for all security-sensitive applications: digital signatures, certificate verification, blockchain, and any context where collision resistance matters.
Pros & Cons
MD5
Faster computation
Shorter hash output
Sufficient for non-security checksums
Broken for security use
Not recommended by NIST
SHA-256
Cryptographically secure
No known collision attacks
Industry standard
Slower than MD5
Longer hash output
Verdict
SHA-256 for anything security-related. MD5 only for legacy compatibility or non-security checksums. There's no good reason to choose MD5 for new projects.