MD5 hash
Compute a MD5 digest of any file, on your device.
Runs on your device. The file is never uploaded.
MD5 hash digests any file into 128 bits, which print as 32 lowercase hex characters below a line carrying the algorithm and your file name. The same hash-wasm md5 call backs the JA3 and HASSH fingerprints here, where the specifications fix that choice. Collisions are cheap to construct, so a match settles nothing about a file someone might swap.
Questions
Is MD5 secure?
No. MD5 is cryptographically broken. Collisions can be produced cheaply, which means two different files can be made to share one MD5, so it proves nothing about a file an attacker might have influenced. Do not use it for signatures, for password storage, or to decide that a download was not tampered with. Use SHA-256 hash for that.
What is MD5 still fine for?
Matching a value somebody else already published in MD5, checking that a copy or a transfer did not corrupt a file by accident, and de-duplicating your own files where nobody is trying to trick you. It also survives inside protocols that define it, such as the JA3 and HASSH fingerprints on this site, where MD5 is part of the specification rather than a security choice.
How long is an MD5 digest?
128 bits, printed as 32 lowercase hex characters. The tool prints the title, two spaces and your file name on the first line, then the digest on the second. There are no options to set, so the same file always gives the same result.
Can I hash several files at once?
Yes. Drop as many as you like. Each file is hashed on its own and comes back as its own result, so twenty files in means twenty digests out. The hashing itself is hash-wasm, a WebAssembly build, running in a Web Worker in this tab.
Why does my MD5 not match the one from another tool?
MD5 is fully specified, so a mismatch means the two runs saw different bytes. The usual causes are a text file saved with Windows line endings on one side and Unix line endings on the other, a trailing newline your editor added, or the other tool hashing a pasted string rather than the file. Hash the exact same file in both places to confirm.