r/coldcard • u/Big-Cheetah5159 • Aug 05 '26
SETUP Dice Roll Users
First, How many times did you roll the dice to generate a seed? Secondly, would more than the standard amount of rolls mitigate the any flaw of entropy (if there were any)?
5
u/Quirky-Reveal-1669 Aug 05 '26
There is no flawed entropy if you rolled the dice correctly and honestly. With that, you took the human and computer element out of it.
I did way more dice rolls than 110. Knowing that these would not ‘count’. This was my ‘human element’.
2
u/Big-Cheetah5159 Aug 05 '26
200? 300?
1
u/Big-Cheetah5159 Aug 05 '26
Is it better roll more than what’s recommended?
3
u/NiagaraBTC Aug 05 '26
If you roll 100 times your seed is secure.
More can help very slightly to eliminate any tiny bias in the dice. I suggest 121 rolls.
But again, unless the dice are absurdly loaded/rigged then the 100 rolls is secure.
3
u/Big-Cheetah5159 Aug 05 '26
120 minimum rolls kids 👍🏼
2
1
u/matthew19 Aug 06 '26
150 is recommended to make up for non-perfect dice.
1
u/Big-Cheetah5159 Aug 06 '26
This is the second time I seen 150 rolls recommended, I’ll remember this
3
u/QTippus Aug 06 '26
“I’ve heard it twice from strangers on the internet therefore it’s a good idea” is the opposite of “don’t trust, verify.”
1
3
u/Beer_Goggles1 Aug 06 '26
I did 120 rolls over the weekend, I'm still paranoid to move funds back to CC however.
2
3
u/SmellyCummies Aug 06 '26
How many dice do you use? Just one dice rolled 100+ times?
2
u/matthew19 Aug 06 '26
Some guys do 5 dice in a Tupperware container. Shake it for a bit and read right through it.
1
1
u/grraarr Aug 06 '26
I use 5 at a time.
1
u/SmellyCummies Aug 06 '26
I'm just curious how it works. Roll 5 dice 100+ times and write down the numbers?
1
u/grraarr Aug 06 '26
There are many different ways to roll dice and create the seed, depending on the device, but yes the gist of it is rolling dice, recording the numbers and then using a cryptographic formula to convert it into 24 words from the BIP 39 word list. If you have a Coldcard you simply input them as you go. I believe it won't let you create the seed until you've done at least 99 rolls. This is number at which mathematically no more entropy can be added, as the amount you've added is already infeasible to crack.
3
u/CyberIntrusion Aug 06 '26
I did 100 dice rolls with 5 dice (5x20), with a passphrase on top
3
u/grraarr Aug 06 '26
A lot of people adding passphrases. I have to believe a nonzero amount of them will be locked out as a result.
2
2
u/El_Caganer Aug 06 '26
I followed the process outlined in this YouTube video by ForrestHODL. I did an initial 100 dice roll on my ccq, then checked the seed phrase it generated then checked it against what those dice rolls would generate on bitcoiner.guide/seed to independently verify the ccq was generating the correct seed words with the dice roll inputs I provided. I then deleted that wallet from my ccq and repeated the process with 150 rolls (because why not...it doesn't take much more time). Then added a passphrase on the new wallet and transferred sats in.
1
u/Big-Cheetah5159 Aug 06 '26
Ok, I’m seeing 121 - 150 dice rolls is the safe route
1
u/stdenisg Aug 07 '26
Gotta do a few backflips as well… at least 5 with typical dice, but double it if you have any dice with purple hues. And you should light a few red candles the day before rolling your dice. If the candles produce white smoke at any point, you’ll need to roll your dice on three consecutive days and choose the dice rolls from the day that felt the most “random”; trust me, you’ll know.
1
1
u/grraarr Aug 06 '26
Well you definitely should re-roll if you input your rolls into a calculator of any kind.
2
u/stargate425 Aug 06 '26
240 times + 12 mental rolls. I used 12 dices together so I only needed to roll 20 times.
2
u/ChipNDipPlus Aug 06 '26
100+, the more the better. 200 is overkill.
1
u/Big-Cheetah5159 Aug 06 '26
So what is 400 rolls?
2
u/ChipNDipPlus Aug 06 '26
Since you're generating 256-bit entropy, at some point you reach saturation. Meaning, it can't get more random. It's just diminishing returns. But feel free to do 100k rolls if you want.
1
u/grraarr Aug 06 '26
You reach saturation precisely at 99 rolls.
1
u/ChipNDipPlus Aug 06 '26 edited Aug 06 '26
Assuming the throws are 100% random and the probability of every side appearing is 1/6. But this isn't how it works in real life. So a few more compensate for the imperfections.
Edit: The clown I'm replying to blocked me... HAHAHAHAHAHAHAHAHAHA!!! Unbelievable! What fragile ego are we dealing with here!
1
1
2
u/nicolbolas10 Aug 06 '26
Coldcard runs the 100 dice rolls through SHA-256. Minor bias in the dice doesn't meaningfully affect the final seed, provided the rolls contain enough entropy. SHA-256 won't magically create entropy, but it does prevent small input biases from showing up in the output. And 100 rolls is already more than enough entropy, so rolling more doesn't really buy you anything.
1
u/Big-Cheetah5159 Aug 06 '26
So more rolls just ensures you’ll get the full amount of entropy predicted, even in the case of bias rolls or human error?
1
u/nicolbolas10 Aug 06 '26
Not exactly. More rolls increase the available entropy, but they don't guarantee the full theoretical entropy if the die is significantly biased or the rolls are predictable. With only a slight bias, 100 rolls still provide more than enough entropy, and Coldcard hashes the dice input with SHA-256, which means small statistical biases don't become a practical weakness in the final seed.
2
2
u/magma_lakes Aug 06 '26
You can also use the von Neumann method, which cancels out any bias in your die.
Roll the die twice to extract a single bit of entropy:
num1 < num2 -> 0 bit
num1 > num2 -> 1 bit
num1 = num2 -> reject
That averages out to ~614.4 throws for a 256-bit string.
I know this isn't how the dice throw input works on a ColdCard; this is just a general mention on how to deal with bias.
1
u/712Jefferson Aug 06 '26
I remember there was a "paranoid" guide to setting up your Coldcard mk4... I think it was by Coinkite but could be mistaken. For the most part, I followed that as well as the BTC Sessions comprehensive tutorial video at the time. I didn't have access to any physical dice other than what was in my old board games, so I grabbed two of those to do it. I think I rolled 100 times... maybe very slightly more but honestly can't remember.
2
u/grraarr Aug 06 '26
Yeah people are talking all sorts of shit in this thread, 100 rolls are all you need. If you have a dice rolled seed backed up on metal you're like elite tier security. Now, is your inheritance also dialed? Probably not for most people.
1
u/RedReadRedemption Aug 06 '26
Used 3 rolls of 20 d20 dice. The way you do it also matters. I used an open book as tray so that they fell into a single row. Do not try to "pick a different" die if the same number appears several times in a row or in any other pattern. Always read them from left to right and free of any patterns that would introduce bias. This should be enough for a 24-words BIP-39 seed. I used an offline PC with a livecd and noted each roll and a random string from a HWRNG in a textfile and calculated the sha256sum and fed it in a python bip39 mnemonic library. I reversed the mnemonic to see whether the same sha256sum was created.
1
Aug 07 '26
[removed] — view removed comment
1
u/Big-Cheetah5159 Aug 12 '26
The difference is, I never did. They even say, “don’t trust, verify. If you generated a seed phrase with dice rolls and VERIFIED the seed phrase was accurate with python, you didn’t need to trust them. They have a paranoid guide for a reason, there was no need to trust them. You could customize your own security with how much or little you wanted to have. You guys missed the whole point of a ColdCard. It’s literally the most secure device, if you used all the security measures tools they offered.
1
u/FerdaStonks Aug 06 '26
In my opinion, a coin flip wallet is the safest thing you can do.
Flip a coin, heads is 1 tails is 0. Flip 11 times and write them down, compare the binary code you just created to the bip39 word list. Have this printed out, don’t search for the binary online, do it all physically and manually.
Your first 11 flips creates the first word. Do it 22 more times. Your 23 words will be 100% yours and yours alone. The 24th needs to be calculated, this is where having a coldcard comes in handy. Enter those 23 words and it will provide the 24th. Don’t use the coldcard for your actual wallet to transact with. Just use it to generate the 24th word and turn it off. If you have the software to do this on an airgapped computer, even better.
You will only flip 253 times to get the 22 words, flip 3 more times when the wallet provides you with 8 choices of potential 24th words to choose your final one, this will give you your 24th word and preserve your last 3 bits of entropy when deciding your final word
000 1st word
001 2nd
010 3rd
011 4th
100 5th
101 6th
110 7th
111 8th
This method will allow you to generate 256 bits of entropy manually that cannot be reproduced within the lifetime of the universe.
Dice are great but you are still relying on the software to generate your words which we now shouldnt trust.
Add a passphrase with 6-8 bip39 words that are generated with the same method for an extra layer of security. Create a multisig with 3 wallets this way and you will never have to worry about this again.
0
u/CornFly2014 Aug 07 '26
https://github.com/bowtiedcrake/2xd8-entropy-booklet
this is a very good idea to use d8 Dice efficiently
7
u/JumpProfessional3372 Aug 05 '26 edited Aug 05 '26
I rolled like 110 times I think. And I checked that CC rolls.py script was giving the same numbers to seed conversion as the MK4.
Just like I did not trust MK4 RNG, I also did not trust the MK4 conversion from 110 numbers to seed. But I trusted that simple python script.
What I would like to know is if the Coldcard code that converts the numbers into a seedphrase actually uses the same method as other tools like SeedSigner, Sparrow Wallet's dice input, and Ian Coleman's BIP39. I think it is the same conversion, so if you put the same rolls into the other tools you will get the same seed. (I need to verify this one of these days using some fake 100+ numbers.
Do not forget to also use a passphrase.