MD4 hash generator.

MD4 is a 128-bit hash Ronald Rivest designed in 1990 (RFC 1320), the ancestor of MD5, SHA-1 and RIPEMD. It was built for speed on 32-bit CPUs: three rounds over 512-bit blocks, and it still runs over a gigabyte a second in software.

Completely. Hans Dobbertin found collisions in 1996; by 2004 Wang's attack produced them by hand, and today a full collision takes microseconds. Preimage attacks are also known at reduced cost. It must not be used for anything that needs security.

NTLM. Windows stores a user's password as the MD4 of its UTF-16LE encoding, and NTLM authentication, Kerberos RC4 keys and pass-the-hash attacks all turn on that value; the eDonkey network also identified files by an MD4-based hash. To match an NTLM hash, encode the password as UTF-16LE first; this tool hashes UTF-8.

Only to reproduce a value a legacy system expects, or to study how hash functions evolved. For a checksum, CRC32 or xxHash is faster and honest about what it is; for security, SHA-256 or BLAKE3.

Nothing leaves your browser. The hash is computed on your machine, by the browser's Web Crypto API or a WebAssembly build of the algorithm loaded on first use, and the page makes no request with your input. You can load the page, go offline and keep hashing.

Drop the file onto the input or choose it with the button, and the tool reads it in your browser and hashes the bytes. Files up to 1 GB work; past that the browser would need the whole file in memory, so the tool declines. Paste the published digest into the Verify field to compare.

Hex is the common form: 32 characters from 0 to 9 and a to f, the same value in upper or lower case. Base64 writes the same 16 bytes in fewer characters, and Base64url swaps + and / for - and _ with no padding. Switch the output and the digest is re-encoded, not recomputed.

Text is hashed as UTF-8 bytes, which is what every language and command line does by default. A trailing newline changes the digest, so `echo -n` or this tool's input, with no newline added, matches a command-line tool run on a file without one.

Turn on HMAC and enter the secret: the tool computes HMAC-MD4 over the input with that key, the standard RFC 2104 construction, so the value matches what a server-side HMAC library produces. The key is hashed as UTF-8 text.

No. The MD4 hash generator is free and opens without a sign-in, an account or an install.

Nothing. The MD4 hash generator holds your input in the page's memory, so closing or reloading the tab clears it, and it saves nothing in this browser.

The toolbar switches to MD5, SHA-1, and RIPEMD-160 without leaving the page. Each one reads the same input, so you can compare digests side by side.

MD4 is computed by a WebAssembly build from the hash-wasm library, which the page loads the first time you hash something and reuses after that.

Yes: the File to MD4 page has the same algorithms and options and opens on the file pane. Files are read in your browser and never uploaded.

Not on its own. MD4 is built to be fast, and fast hashes are cheap for an attacker to guess against. Passwords need a salted, deliberately slow hash: use Argon2id, Argon2d, and bcrypt from the hash generators, which draw a fresh random salt each time.

Closest to the MD4 hash generator: File to MD4, MD5 hash generator, SHA-1 hash generator, SHA-256 hash generator. Each opens on its own page, free and in the browser.

The MD4 hash generator is one of 64 in its group. The group's page, /tools/hash, lists them all.

The tool is free. Its interface is built from shadcn.io's own components (Button, Input, Slider and the rest of the registry under /ui), which come in React, Vue, Svelte and Solid. Pro adds the blocks and templates for the product around it.