Yes. When you create a new Bitcoin wallet, the BitBox02 can use entropy that you generate yourself—for example, by rolling dice. Entropy is simply the unpredictable input from which the secret behind your recovery words and wallet keys is created.
For most people, the normal BitBox02 setup is the better choice because it already combines several independent sources of entropy. Generating your own entropy is not an automatic security upgrade; rather, it gives experienced users a way to contribute and verify the randomness used for a new wallet. Because the process is manual, however, a single mistake can weaken the wallet or leave you unable to recover it later.
For a deeper look at the reasoning behind this option and the complete dice-based method, read the BitBox blog post Roll your own Bitcoin seed.
What custom entropy means
At the heart of every Bitcoin wallet is a secret that must be impossible to predict. Your recovery words are the offline, human-readable backup of that secret. If your wallet does not use a passphrase, anyone who obtains those recovery words can recreate the wallet and control its funds.
With custom entropy, you supply the random input while creating a new wallet. Properly used dice are well suited to this because their rolls provide a physical source of randomness. Choosing words, numbers, or patterns that merely seem random is not a safe alternative: people are naturally poor at producing unpredictable choices.
Why the standard BitBox02 setup is suitable for most users
During a normal setup, the BitBox02 combines entropy from factory setup, its secure chip, its microcontroller, the connected computer, and your device password. The sources are combined so that the resulting entropy is at least as strong as the strongest available source.
This layered approach is safer for most users because it avoids the points at which manual methods commonly fail, such as a biased source of randomness, an incorrect record, or a transcription mistake. You can learn more about the design in the BitBox security features.
When custom entropy may be appropriate
Custom entropy can make sense if you have a specific trust-minimisation or verification goal and understand the complete procedure. It matters only while you create a new wallet: it cannot add entropy to, or improve the security of, a wallet you already use.
It also does not replace the security practices that protect your funds day to day. You still need to protect your BitBox02, confirm important details on its screen, and store the resulting recovery words securely.
Advanced setup only
Creating your own entropy is optional. Use the standard BitBox02 setup if you are not confident that you can complete an offline procedure, record the result accurately, and verify the backup afterwards.
Risks of manually created entropy
When you create entropy manually, you take responsibility for every part of the process. Predictable input, a skipped roll, a mistaken lookup, or an incorrect word order can leave you with a wallet that is weaker than intended—or one that cannot be restored later.
Use one documented method from start to finish instead of adapting the process as you go. Work in private, and keep dice results, recovery words, and other intermediate information off phones, computers, cloud services, password managers, and websites.
Recovery words warning
Never enter your recovery words into a computer, smartphone, website, browser extension, password manager, cloud service, or AI chatbot. Anyone who obtains your recovery words can control your Bitcoin.
As part of the supported process, the BitBox02 helps ensure that your recovery words include the required checksum. The final words are therefore not a free choice: a reliable wallet backup needs both sufficient randomness and a valid structure.
How to create a wallet with custom entropy
If you decide to use custom entropy, follow the official BitBox02 Diceware instructions from start to finish. They provide the supported dice method, lookup table, and BitBox02 steps for creating a new wallet offline.
Once setup is complete, verify that you recorded the recovery words correctly, then store the backup offline. For the essential protection rules, see how to securely store recovery words.
Frequently asked questions
Does custom entropy make a BitBox02 wallet more secure?
No, not automatically. Custom entropy can reduce reliance on the BitBox02’s built-in random-number generation, but the standard setup already combines multiple entropy sources. Because a poorly performed manual process can reduce security, this feature is best reserved for users who understand its risks.
Can I choose my own recovery words?
No. Recovery words must encode sufficiently random entropy and include a valid checksum, so familiar words, phrases, or numbers are not safe choices. Use the official dice-based method rather than inventing a word list that may be predictable.
Can I use a custom-entropy wallet with another wallet?
Yes, in most cases. The supported BitBox02 process produces BIP39 recovery words, which a compatible wallet can restore. Before you depend on another wallet for recovery, confirm that it supports BIP39 and the recovery-word length you created.
Can I add custom entropy to an existing wallet?
No. Entropy is used only when a new wallet is created. If you want to use custom entropy, create a new wallet and move funds only after you have verified the recovery words and backup.