MD5 (Message Digest Algorithm 5) produces a 128-bit (32 hex character) hash. While not suitable for security-critical purposes, it is still widely used for checksums and data integrity verification. This tool runs entirely in your browser using a pure-JavaScript MD5 implementation.
MD5 (Message Digest 5) was designed by Ron Rivest in 1991 and standardised as RFC 1321. It produces a fixed 128-bit fingerprint of arbitrary input — written here as 32 lowercase hex characters. MD5 is no longer considered cryptographically secure (Wang and Yu published practical collisions in 2004) but remains widely used for non-adversarial work such as cache keys, ETags, deduplication and detecting accidental file corruption.
The page implements MD5 in pure JavaScript directly from the RFC 1321 reference: it UTF-8-encodes the input to bytes, applies the standard 64-step compression function (the FF/GG/HH/II auxiliary functions across four rounds of sixteen operations) and emits the four 32-bit state words as little-endian hex. Everything runs in your browser; the input string is never transmitted. Output matches `md5sum`, `openssl md5`, PowerShell's `Get-FileHash -Algorithm MD5` and Python's `hashlib.md5(s.encode()).hexdigest()`.
Not for anything security-sensitive. MD5 has been broken since Wang & Yu published a collision attack in 2004 and HashClash now generates colliding pairs in seconds. It is fine for non-adversarial use cases such as cache keys, ETags, deduplication and file-integrity checks against accidental corruption — never for password hashing, digital signatures or content authentication.
Lowercase hex — 32 characters representing the 128-bit digest, the same format produced by md5sum, openssl md5 and PowerShell's Get-FileHash -Algorithm MD5. Re-encode to Base64 with btoa() if you need the 22-character form.
Yes for plain text. The page UTF-8-encodes the string before hashing, which matches printf '%s' "text" | md5sum. Note the difference: echo "text" | md5sum appends a trailing newline and produces a different digest.
The input is encoded to UTF-8 bytes before the MD5 transform runs, so "café" becomes the four-byte sequence 63-61-66-C3-A9 and emoji like 🍕 hash as their multi-byte UTF-8 representation — the same bytes a server-side library would see.
Explore the full suite of HASH & CRYPTO tools and 290+ other free utilities at Chunky Munster.
📖 Reference: RFC 1321 — The MD5 Message-Digest Algorithm