yEnc is very much designed specifically for Usenet though. It gets its low overhead largely from using almost all characters which aren't special in NNTP (and a

yEnc is very much designed specifically for Usenet though. It gets its low overhead largely from using almost all characters which aren't special in NNTP (and also adapts allowed characters depending on NNTP context), which isn't appropriate for many cases where base64 is used. There's encodings which may be more appropriate, which use more than 64 codepoints, such as base85 (https://en.wikipedia.org/wiki/Ascii85 https://en.wikipedia.org/wiki/Ascii85), assuming that these are allowed. As an aside, I've implemented a fast SIMD accelerated yEnc encoder/decoder here (https://github.com/animetosho/node-yencode https://github.com/animetosho/node-yencode), for anyone interested.