Developed by Ronald Rivest in 1991, MD5 was designed to replace its predecessor, MD4. It produces a 128-bit hash value (32 hexadecimal characters). For nearly two decades, it was the standard for checksums, password storage (with salts), and digital signatures.
The Fall: In 1996, collisions (two different inputs producing the same output) were found. By 2008, researchers demonstrated a practical collision attack against the Certificate Transparency log. Today, MD5 is considered "cryptographically broken." You should never use it for security.
Let’s be unequivocal: MD5 is cryptographically broken for collision resistance. The attacks are not theoretical: xxhash vs md5
The only reason MD5 persists is:
xxHash makes no security promises. But unlike MD5, it also doesn’t pretend to be secure. The true comparison is not “xxHash vs MD5” for security — it’s “SHA-256 vs MD5” where SHA-256 wins entirely. Developed by Ronald Rivest in 1991, MD5 was
The industry has largely settled on a two-tiered hashing strategy:
Should you ever write new code using MD5?
Generally, No. If you need a 128-bit checksum, use xxHash128. It is faster and provides better statistical distribution than MD5. The only reason to use MD5 today is to read legacy data or maintain a legacy protocol. The only reason MD5 persists is:
Final Verdict:
Stop using MD5 for new projects. If you need speed, reach for xxHash. If you need safety, reach for SHA-256. The era of "one hash to rule them all" is over.