Both encodes and decodes base64 encoded data. Input and output can either be text or a file. Note that the entirety of the data is loaded into memory, so you don't want to be converting huge globs of data (though I'm not sure what the user case for base64 with large data blobs would be, but I'm not the masochist you are). The code is open source and you are more than welcome to download and build it yourself, but if you want the convenience of just running it (and any updates that I might add easily available), you can purchase a copy here. The code is available at https://github.com/mredig/B64