Free MD4 Hash Generator — Create MD4 Checksums Online Instantly

What Is an MD4 Hash Generator?

An MD4 hash generator converts any text into a fixed 128-bit (32-character hexadecimal) hash value using the MD4 (Message Digest 4) algorithm. Created by Ronald Rivest in 1990, MD4 was designed as a faster successor to MD2 and became the foundation for both MD5 and the SHA family. Our free online tool generates MD4 hashes instantly — no downloads needed.

Why MD4 Hashing Is Important

Although MD4 is no longer considered secure for cryptographic applications, it remains historically significant:

• Foundation of modern hashing — MD4's design influenced MD5, SHA-0, SHA-1, and RIPEMD
• NTLM authentication — Windows NTLM password hashing is based on MD4
• Legacy protocol support — Some older systems and file-sharing protocols still use MD4
• Educational value — Understanding MD4 helps grasp how modern hash functions evolved

How MD4 Works

The Algorithm in Detail

1. Padding: The message is padded to ensure its length is 64 bits less than a multiple of 512
2. Length Append: The original message length (64-bit) is appended
3. Initialize Buffers: Four 32-bit registers (A, B, C, D) are initialized with specific constants
4. Process Blocks: Each 512-bit block is processed through 3 rounds of 16 operations each, using bitwise functions (AND, OR, XOR, NOT)
5. Output: The concatenation of the final register values produces the 128-bit hash

MD4 vs MD2 vs MD5

• MD2: Byte-oriented, slow, designed for 8-bit processors
• MD4: 32-bit optimized, fast, 3 rounds — but vulnerable to collision attacks
• MD5: Enhanced MD4 with 4 rounds and additional complexity — more collision-resistant but also now broken

How to Use Our Free MD4 Generator

1. Type or paste your text into the input box above
2. Click Generate
3. Copy your MD4 hash result instantly

Common Use Cases

• NTLM hash analysis: Security researchers analyzing Windows authentication hashes
• Legacy system maintenance: Working with older protocols that require MD4
• Cryptographic research: Studying collision attacks and hash function design
• File identification: ED2K (eDonkey) file-sharing network uses MD4 for file hashing
• Cross-algorithm testing: Comparing hash outputs across the MD family

Security Considerations

MD4 is cryptographically broken. Collision attacks can be performed in fractions of a second on modern hardware. Do not use MD4 for:

• Password storage — use bcrypt instead
• Digital signatures or certificates
• Data integrity in security-critical applications

For secure hashing, use SHA-256 or SHA-3.

Best Practices

• Use MD4 only for legacy compatibility or research
• Migrate any systems still using MD4 to SHA-256 or stronger algorithms
• For password hashing, always use purpose-built functions like bcrypt or Argon2
• Document any MD4 usage in your systems for future migration planning

Related Tools

• MD2 Hash Generator — Generate MD2 checksums
• MD5 Hash Generator — The most popular MD-family hash
• SHA-1 Generator — Create SHA-1 hashes online
• SHA-256 Generator — Secure 256-bit hashing
• Password Generator — Create strong random passwords

Frequently Asked Questions

Is MD4 the same as MD5?

No. MD4 and MD5 are related but different algorithms. MD5 was designed as an improved version of MD4 with an additional round of processing and stronger diffusion. Both produce 128-bit hashes, but MD5 offers better collision resistance (though both are now considered broken).

Why is MD4 still used in Windows NTLM?

Windows NTLM authentication uses MD4 for historical reasons — it was implemented before MD4's vulnerabilities were fully understood. Microsoft has been encouraging migration to Kerberos and more modern authentication methods, but NTLM persists in many enterprise environments for backward compatibility.

Can MD4 hashes be cracked?

Yes. MD4 collision attacks are trivial on modern hardware, taking less than a second. For password hashes, rainbow tables and brute-force attacks are highly effective against MD4. This is why it should never be used for security purposes.

What should I use instead of MD4?

For general-purpose hashing, use SHA-256. For password storage, use bcrypt, scrypt, or Argon2. For file integrity, SHA-256 or SHA-3 are recommended.