MD4 Hash Generator Online — Free MD4 Checksum Tool
Use this free online MD4 hash generator to compute an MD4 checksum from any text string or file upload — paste text or provide a local or remote file URL, and get the hash in seconds.
What is MD4?
MD4 (Message Digest 4) is a cryptographic hash function designed by Ron Rivest in 1990. It produces a fixed-length 128-bit (16-byte) digest from any input, regardless of its size. MD4 was an influential early hash algorithm and served as the direct predecessor to the more widely known MD5 algorithm. Like all MD-family hashes, it processes input in 512-bit blocks and outputs a compact hexadecimal string.
It is important to note that MD4 is considered cryptographically broken. Serious collision vulnerabilities were demonstrated as early as 1995, meaning two different inputs can be crafted to produce the same hash. MD4 should therefore never be used for password storage, digital signatures, or any security-sensitive application.
What is MD4 used for today?
Despite its cryptographic weaknesses, MD4 still appears in specific legacy and compatibility contexts:
- NT LAN Manager (NTLM): Windows authentication protocols historically used MD4 as the basis for NT password hashes, so understanding MD4 is relevant for network security research and penetration testing.
- Checksums on trusted data: When both parties are trusted and collision resistance is not required, MD4 can serve as a fast checksum to detect accidental data corruption.
- Educational and research use: MD4 is widely studied in cryptography courses and research as a historical example of hash function design and its pitfalls.
- Legacy software compatibility: Some older protocols and systems that predate MD5 adoption may still reference MD4 digest values.
HMAC-MD4 and keyed hashing
This tool also supports HMAC (Hash-based Message Authentication Code) with the MD4 algorithm. HMAC combines a secret key with the hash function to produce a message authentication code, verifying both data integrity and the authenticity of the sender. Even so, HMAC-MD4 is not recommended for new security designs — prefer HMAC-SHA256 or stronger alternatives in production systems.
Frequently asked questions
Is this MD4 hash generator free to use?
Yes, it is completely free. No account, subscription, or signup is required — simply enter your text or upload a file and generate the MD4 hash instantly.
Can I hash a file as well as text?
Yes. You can type or paste text directly, upload a file from your device, or provide a URL to a remote file. The tool will compute the MD4 hash over the full file content.
How are uploaded files handled? Is my data private?
Files uploaded to the tool are processed on the server solely to compute the hash and are deleted automatically afterwards. They are not stored, shared, or used for any other purpose.
Is MD4 safe for securing passwords or sensitive data?
No. MD4 is cryptographically broken and must not be used for password hashing, digital signatures, or any security-critical purpose. Use it only for non-security tasks such as legacy checksums or educational purposes.
What is the difference between MD4 and MD5?
Both produce a 128-bit digest, but MD5 (released 1992) added an extra round of processing to improve security over MD4. MD5 is also considered cryptographically weak for security use, but is still widely used as a non-security checksum — and both are far weaker than modern algorithms like SHA-256.