MD5 hash generator
Type or paste any text to compute its MD5 digest instantly. Everything runs client-side in your browser.
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What MD5 is
MD5 (Message Digest Algorithm 5) is a hash function published in 1992 that takes an input of any length and produces a fixed 128-bit (32 hexadecimal character) digest. For decades it was the default choice for checksums, file verification, and — mistakenly, in hindsight — password storage. It's still extremely common today, just not for anything security-sensitive.
What MD5 is still good for
- File integrity checks. Confirming a downloaded file wasn't corrupted in transit by comparing its MD5 checksum to one published by the source.
- Non-cryptographic deduplication. Quickly identifying duplicate files or cache entries where an attacker deliberately engineering a collision isn't a realistic threat.
- Legacy system compatibility. Many older systems and file formats (ETags, some VCS internals, older CMS password columns you're migrating away from) still use MD5 and you need to reproduce or inspect that value.
What MD5 is not good for
MD5 has been cryptographically broken since the mid-2000s: researchers can deliberately construct two different inputs that produce the identical MD5 hash (a "collision"), which undermines any use case that depends on MD5 being tamper-evident, such as digital signatures or certificate validation. It's also far too fast to use for password storage — see our password hash generator guide for what to use instead, or jump straight to bcrypt for passwords.
MD5 and password recovery
Because MD5 was so widely used for password columns in the 2000s and 2010s, huge precomputed lookup tables of MD5 hashes for common passwords circulate publicly. This is why "cracking" a bare MD5 hash of a weak password is often trivial — not because MD5 is mathematically reversible (it isn't), but because the input space of common passwords is small enough to have already been hashed and indexed. Try this yourself, safely, with our MD5 decrypt / dictionary lookup tool.
Adding a salt to MD5
If you have a legacy reason to keep using MD5 for anything sensitive, always combine it with a unique random salt — see our MD5 hash generator with salt for append, prepend, and HMAC variants, plus an explanation of which approach is strongest.
Frequently asked questions
Is MD5 encryption?
No. MD5 is a one-way hash function, not encryption. Encryption is reversible with a key; hashing is not reversible by design.
Can I use MD5 to check if a file downloaded correctly?
Yes — comparing the MD5 checksum of a downloaded file against the one published by its source is still a common and reasonable use of MD5, since accidental corruption (not a deliberate attacker) is the threat being guarded against.
Why do two different strings sometimes have the same MD5 hash?
This is called a hash collision. MD5 has known, practical collision attacks, which is one of the main reasons it is no longer considered safe for digital signatures or certificate validation.