Different results between int and String

[Sulley93]

If I call md5 with an integer parameter it return a different value from md5 called with a string parameter.
e.g.
md5(1003) = 64e0407ffc70c04a366526a7065cbd05
md5('1003') = aa68c75c4a77c87f97fb686b2f068676.

Is it a normal behavior?

[pvorb]

Yes, this is "normal". Don't use this library. It will happily help you shoot yourself in the foot.

MD5 is an algorithm that is defined on binary input data. This library just does whatever your runtime will do to make your input binary. So, if your runtime will serialize strings in UTF-16 rather than UTF-8, you'd get different results for the same input string.

[bybraveHQ]

This happens because a raw number isn't a string/Buffer/Array/Uint8Array, so it hits message.toString() and then the byte converter reads the resulting string in a way that doesn't match how a normal string is encoded — hence md5(1003) !== md5('1003').

In a maintained fork I coerce number/object input to String(value) before hashing, so md5(1003) === md5('1003') (predictable and documented):

@bybrave/md5 — drop-in for string/Buffer/Uint8Array (byte-for-byte identical digests), zero runtime deps, ESM + CJS, built-in TypeScript types.