A collision occurs when two different inputs produce the same hash output. A cryptographically secure hash must make finding collisions computationally infeasible.
MD5 has known real-world collisions. SHA-256 currently has no practical collision attacks.
Type text below and compare how MD5 and SHA-256 generate different hashes.
Enter 5 different text inputs to see how hash generation time varies for each algorithm. The test will run 10 iterations per input for accurate results.
Hash Length: 128 bits
Security: BROKEN (collisions found in 2004)
Status: Deprecated by NIST
Real Attacks: Multiple (e.g., Flame malware 2012)
Performance: Faster
Modern Use: Legacy checksums only
Hash Length: 256 bits
Security: No known collisions
Status: NIST approved (FIPS 180-4)
Real Attacks: None
Performance: Slightly slower (~30%)
Modern Use: Bitcoin, SSL/TLS, Code signing
MD5 is faster but insecure due to proven collisions. SHA-256 is slightly slower but secure against collision attacks.