[planede]

base10 can be awkward to work with for large data, one can also consider:

base8 in numeric mode: 8 input bits -> 3 digits -> 10 output bits, 25% overhead

base32 in alphanumeric mode: 5 input bits -> 1 character -> 5.5 output bits, 10% overhead

I would prefer base32 out of these too, but it's interesting that even base8 beats base64 here.

[dbaupp]

Good point! I've added an analysis of this and other bases to https://huonw.github.io/blog/2024/03/qr-base10-base64/#fn:ot...

[planede]

Doh! I don't know why I went with per-byte encoding for octal. Yeah, you can do 11.1% overhead with base8, not much worse than base32, surprisingly.