Any time base conversion comes up, I shamelessly plug my arbitrary base converter: https://convert.zamicol.com https://convert.zamicol.com The base64 under "u

Any time base conversion comes up, I shamelessly plug my arbitrary base converter: https://convert.zamicol.com https://convert.zamicol.com The base64 under "useful alphabets" is the "natural", iterative divide by radix, base. There's the RFC's "bucket" conversion base under extras.