Hawkynt

MD5

128-bit cryptographic hash function designed by Ronald Rivest. Fast but cryptographically broken with practical collision attacks.

Properties

Property	Value
Category	Hash Functions
Sub-category	MD Family
Security status	❌ Broken
Complexity	Beginner
Inventor	Ronald Rivest
Year	1991
Origin	🇺🇸 United States
Source	algorithms/hash/md.js

Parameters

Parameter	Supported values
Output sizes	16 bytes (128 bits)

Security

Status: ❌ Broken

Known vulnerabilities

Issue	Description	Mitigation
Collision Attack	—	Practical collision attacks demonstrated by Wang et al. in 2004. Can generate two different messages with same MD5 hash.
Chosen-prefix Collision	—	Attackers can create collisions with chosen prefixes, enabling sophisticated attacks.
Rainbow Table Attack	Common passwords vulnerable to precomputed rainbow table attacks.	—

Documentation

• RFC 1321 - The MD5 Message-Digest Algorithm
• NIST SP 800-107 - Recommendation for Applications Using Approved Hash Algorithms
• Wikipedia - MD5

References

• OpenSSL MD5 Implementation
• MD5 Collision Research
• RFC 6151 - Updated Security Considerations for MD5

Test vectors

7 vectors ship with this algorithm and run in the test suite. Byte values are hexadecimal.

Vector 1 — RFC 1321 Test Vector - Empty string

Field	Value
input	(empty)
expected	d41d8cd98f00b204e9800998ecf8427e

Vector 2 — RFC 1321 Test Vector - ‘a’

Field	Value
input	61
expected	0cc175b9c0f1b6a831c399e269772661

Vector 3 — RFC 1321 Test Vector - ‘abc’

Field	Value
input	616263
expected	900150983cd24fb0d6963f7d28e17f72

Vector 4 — RFC 1321 Test Vector - ‘message digest’

Field	Value
input	6d65737361676520646967657374
expected	f96b697d7cb7938d525a2f31aaf161d0

Vector 5 — RFC 1321 Test Vector - alphabet

Field	Value
input	6162636465666768696a6b6c6d6e6f707172737475767778797a
expected	c3fcd3d76192e4007dfb496cca67e13b

Vector 6 — RFC 1321 Test Vector - alphanumeric

Field	Value
input	4142434445464748494a4b4c4d4e4f50 5152535455565758595a616263646566 6768696a6b6c6d6e6f70717273747576 7778797a30313233343536373839
expected	d174ab98d277d9f5a5611c2c9f419d9f

Vector 7 — RFC 1321 Test Vector - numeric sequence

Field	Value
input	31323334353637383930313233343536 37383930313233343536373839303132 33343536373839303132333435363738 39303132333435363738393031323334 35363738393031323334353637383930
expected	57edf4a22be3c955ac49da2e2107b67a

---

← All algorithms

This site is open source. Improve this page.