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0 pointsfauigerzigerk2y ago0 comments

>Is there a good reason why Base63 (nopad) doesn't exist? Ie Base64 minus the `-`, so that you almost get the density of base64 (nopad) but the double click friendly feature.

Yes, the reason is that you need 64 characters if you want each character to encode 6 bits as log2(64) == 6. If you only have 63 characters in your alphabet then one of your 6-bit combinations has no character to represent it.

Base32 can represent 5 bits per character because log2(32) == 5. Anything in between 32 and 64 doesn't buy you anything because there is no integer between 5 and 6.

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unshavedyak2y ago

Is that "just" a performance concern though? Ie why is there a base58 and base62 but no base63?

Now you've got me curious on the performance of base58 to base64 hah. Down the rabbit hole i go. Appreciate your reply, thanks :)

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0 pointsfauigerzigerk2y ago0 comments

>Is there a good reason why Base63 (nopad) doesn't exist? Ie Base64 minus the `-`, so that you almost get the density of base64 (nopad) but the double click friendly feature.

Base32 can represent 5 bits per character because log2(32) == 5. Anything in between 32 and 64 doesn't buy you anything because there is no integer between 5 and 6.

0 comments

unshavedyak2y ago

Is that "just" a performance concern though? Ie why is there a base58 and base62 but no base63?

Now you've got me curious on the performance of base58 to base64 hah. Down the rabbit hole i go. Appreciate your reply, thanks :)

j / k navigate · click thread line to collapse