Dice & Coin Seed Simulator - Bitcoin Northern Beaches

From physical randomness to words

1Create entropyA coin supplies 0 or 1. For dice, odd becomes 0 and even becomes 1.

2Build word indexesEvery 11-bit group selects one word from the 2,048-word BIP39 list.

3Add the checksumThe final word combines the last entropy bits with a SHA-256 checksum.

4Explore addressesOptionally derive example BIP44, BIP49, BIP84 and BIP86 addresses.

How the arithmetic works: the positions in an 11-bit row are worth 1024, 512, 256, down to 1. Multiply each position by its 0 or 1, then add the results. The total is the zero-based index; add one to find the word number in the published list.

Step 1

Create the entropy

Official BIP39 word list ↗

Phrase length Input method

Step 2

Find the checksum word

The final word is partly entropy and partly checksum. Review every structurally possible ending, then test your understanding by entering the checksum-valid word.

Candidate bits	Zero-based index	BIP39 word no.	Possible word

Checksum-valid final word

Step 3

Entropy and checksum

Derive the words

#	Bits	Index	Word no.	BIP39 word	Source

Completed practice mnemonic

A valid checksum does not make a phrase secure.Predictable or website-entered entropy must never hold real bitcoin. The checksum detects some errors; it adds no randomness.

Optional

Example receive addresses

Derive the first five mainnet receive addresses for four standard script types. This happens locally, only when requested, and uses an empty BIP39 passphrase.

Inspired by the educational simulator from TimechainIndex. This independent implementation fixes Taproot encoding and runs without third-party code or analytics.