EDUCATIONAL BITCOIN TOOL

Dice Roll & Coin Flip Simulator

Turn physical coin flips or dice rolls into a BIP39 mnemonic, one word at a time.

Educational purposes only. Seeds generated here must never be used in real life to receive funds. This page derives sensitive wallet material in your browser; use made-up practice rolls and never enter a real recovery phrase. For any real-funds wallet process, work offline in a secure, trusted environment. The binary totals, word indexes, and checksum work can also be performed with pen and paper.

How this lesson works

1. Create entropyEach coin flip gives one bit: 0 or 1. A die gives one bit when odd is 0 and even is 1.

2. Find wordsEvery group of 11 bits is a number from 0–2047. Add 1 to display its BIP39 word-list index.

3. Solve the final wordThe last word contains the remaining random bits plus the checksum. We list every possible completion for you to try.

4. VerifyYour wallet device should accept only the candidate with a valid BIP39 checksum.

How binary becomes a number and word: read the 11 bits as a base-2 number. The 11 positions use 2^10 down to 2^0; 2^11 would be a twelfth position. Multiply each entered 0 or 1 by the value above its box, then add all the results. For example, 00000000001 = 1. That zero-based total points to the second word in the official list, so the displayed BIP39 index is total + 1 = 2.

Phrase length Input method

Enter each word's bits

Open the official BIP39 English word list ↗ Use the BIP39 index shown below to find each word. Download printable 12/24-word worksheets ↓

WordEnter results11-bit groupTotalBIP39 IndexWord

Final word: try every checksum possibility

The last word is special. You entered only the random entropy bits at its beginning. BIP39 fills the remaining bits with the checksum. The simulator will now show every possible completion.

Hardware-wallet note: your hardware wallet may already contain the BIP39 word list or checksum validation that can help you identify the accepted final word. Use this only for education on a new, empty device. Never enter a real funded wallet’s recovery phrase into this simulator, an online service, or an unfamiliar device.

Copy the first words and one candidate final word into your device.
Try the candidates one at a time. For 12 words there are 16 possibilities; for 24 words there are 256.
Your device should accept only the candidate whose checksum is correct.
Enter the accepted candidate below to continue the lesson.

The table's Total is the zero-based binary value (0–2047). The BIP39 index is that same value plus 1 because the published word list is numbered from 1. A candidate is possible because its first bits match your rolls; only one candidate has the correct checksum for the complete phrase.

Candidate bits	Total	BIP39 index	Possible final word

Accepted final word

1. Entropy and checksum

The entropy is divided into 11-bit groups. Each group is interpreted as a number from 0 to 2047, then that zero-based number selects a word from the 2048-word BIP39 English list.

2. Derive the words

#	Bits	Decimal index	BIP39 word	Meaning

3. Final mnemonic

Passphrase warning: adding a passphrase creates an additional layer of protection, but every passphrase is valid. Wallets will not warn you if the passphrase is misspelled or uses different capitalization; a different passphrase creates a different wallet. Make a physical backup of the seed phrase and a separate physical backup of the passphrase, and store them separately.

The final word includes the remaining entropy bits plus the checksum bits. The checksum makes accidental errors detectable; it does not add randomness.

4. First five receive addresses optional advanced output

These use standard mainnet paths: m/44'/0'/0'/0/i, m/49'/0'/0'/0/i, m/84'/0'/0'/0/i, and m/86'/0'/0'/0/i.