MD5 vs SHA-256
Both produce fixed-length digests from arbitrary input, but their security profiles differ dramatically.
| Property | MD5 | SHA-256 |
|---|---|---|
| Output length | 128 bits (32 hex chars) | 256 bits (64 hex chars) |
| Speed | Very fast | Fast (slightly slower) |
| Collision resistance | Broken (collisions found in 2004) | Secure (no known collisions) |
| Pre-image resistance | Weakened | Strong |
| Year introduced | 1992 | 2001 |
| Use for passwords | Never | Not ideal (use bcrypt/argon2) |
| Use for integrity | Legacy only | Recommended |
When MD5 is still acceptable
- Non-security checksums (cache busting, deduplication)
- Legacy systems that require it
- Quick file comparison (not adversarial)
When to use SHA-256
- Any security-sensitive hashing
- Digital signatures and certificates
- Blockchain and cryptocurrency
- File integrity verification
- HMAC for API authentication
Bottom line
Default to SHA-256 for everything. Only use MD5 when backward compatibility demands it and security is not a concern. Generate both with our Hash Generator.