Is it Decryptor or Decrypter? [duplicate]

I'm coding a decryption service and wondering which is the best name, Decryptor or Decrypter I had a quick look online and it appears -er and -or convert a verb to an agent noun, however is one preferable over the other?

Interestingly my Mac tells me to use the latter.

Solution 1:

Based on the comments, especially the references from @choster I think it's fair to say neither are wrong per se; however Decrypter seems to be the slightly better option because it's the more common form (especially in Great Britain), and in my case it's a tool rather than a person doing the decrypting.

Solution 2:

Both seem to be in use (looking at documentation for various tools online). According to Google Ngrams "-or" is very slightly more popular. Although only "-er" occurs in the British English sources. I'm not sure how much Google Ngrams can be trusted for the, though.

I would choose one and stick with it consistently.