Generate Your Seed Phrase Offline with Dice and Blockstream Jade

Why Use Dice?

Generating your seed phrase with dice removes the need to trust any hardware or software with your initial entropy. You create the randomness yourself, completely offline. Interestingly, while we use the Blockstream Jade to calculate the final checksum word, you aren't locked into this device. Once generated, you can recover this seed phrase into any BIP39 compatible wallet you prefer.

What You Will Need

• A Blockstream Jade hardware wallet (factory reset).
• Two 16-sided dice and one 8-sided die. (Note: If you can't find 16-sided dice, 20-sided dice will work just fine. You just have to re-roll any results of 17, 18, 19, or 20).
• The official Blockstream Jade Dice Roll Instructional Guide.
• A printed copy of the Jade Seed Word Index. Always print this off rather than reading it on a screen to protect against malware logging your viewing habits!

Step-by-Step Dice Rolling

1. Roll the Dice: Shake your two 16-sided (or 20-sided) dice and one 8-sided die vigorously and drop them. Read them from left to right. For example, you might roll a 4, a 13, and a 6.
2. Lookup the Word: Using your printed Jade Seed Word Index, follow the columns for D1 (e.g., 4), D2 (e.g., 13), and D3 (e.g., 6) to find your word. Write it down.
3. Handle Invalid Rolls: If you are using 20-sided dice and roll a 17, 18, 19, or 20, that roll is invalid. Scoop all the dice up and re-roll completely.
4. Repeat: Continue this process until you have 11 valid words (for a 12-word seed) or 23 valid words (for a 24-word seed). Leave the final slot blank.

Calculating the Final Checksum on the Jade

You cannot roll all 12 or 24 words because the final word acts as a mathematical checksum. This is where the Blockstream Jade comes in.

1. Turn on your factory-reset Jade and navigate to Setup Jade > Advanced Setup > Restore Wallet.
2. Select 12 or 24 words depending on what you rolled.
3. Carefully input your 11 or 23 words using the scroll wheel. (It can be tedious, but it gets the job done securely).
4. After entering your words, the device will prompt you for the final word. Select Calculate.
5. The Jade will process and offer you a list of valid final words. Pick one and write it down immediately! If you forget this calculated word, you will have to enter all your previous words into the device again.

Next Steps and Self-Custody

Once you have your complete seed phrase, you can connect your Jade to a compatible wallet app and generate your wallet. Remember, because this seed was generated completely offline, you can theoretically import it into any other BIP39 wallet if you prefer a different interface or form factor.