This is a public response for "dice keys overshoot the template" who sent me an email without a return address (probably for privacy/paranoia reasons, totally understandable.) Some other folks might find this helpful too.

Regarding using the "enter your own dice rolls, card shuffles, etc." feature of https://bitcoinpaperwallet.com you wrote:

Hi, When I put in a 64 hexademical dice rolled key, it can't be printed properly as it overshoots the template… such as 8010B1BB119AD37D4B65A1022A314897B1B3614B345974332CB1B9582CF03536 Hope you can fix it Thanks and keep up the good work.

It looks like when you use those hexadecimal dice, you're producing a valid WIF-format private key, which the wallet diligently tries to output just so.

The work-around for you is just to add one character so that your roll is instead interpreted as the source for a SHA-256 hash.

So try this instead:

Z8010B1BB119AD37D4B65A1022A314897B1B3614B345974332CB1B9582CF03536

As I understand, this does not decrease the “randomness” of your roll at all. (Adding the letter might even increase your entropy by a few bits, though I doubt it as your string looks like it pretty much maxes out the usable characters for a SHA-256 hash.)

More importantly, this will cause your roll to be converted into a more typical private key format, which (1) will print better, and (2) is probably more compatible for being imported into various wallets/exchanges/etc.

Hope this helps!

• Canton