Dice Rolls & Entropy

Generate a verifiably random Bitcoin seed phrase using physical dice.

What Is Entropy?

The size of the pool your randomness is drawn from.

Entropy is the measure of unpredictability behind your seed. The bigger and more random the source, the harder your seed is to guess. Think of it as drawing a single atom from a pool — the larger the pool, the more possible atoms, and the more secure the draw.

Ideal Seed Entropy

An atom drawn from the entire universe

The gold standard — randomness so vast it could never be guessed or reproduced. This is the ideal every seed aims for: an entropy source with more possible outcomes than there are atoms in the cosmos.

A Bucket of Water

An atom drawn from a bucket (still searchable)

Better, but still finite. The pool is larger than a single drop, yet a determined attacker could in principle search through it. Usable, but not the strongest foundation.

A Single Drop

An atom drawn from a single drop of water

Weakest. The pool of possibilities is so small that the resulting seed can eventually be found by brute force — no matter how random the words look.

Physical dice rolls let you create entropy yourself, from a source you can see and trust. Enough fair rolls give you a pool large enough to approach the “entire universe” ideal — far beyond anything an attacker could ever search. That is why rolling your own dice, and converting the rolls offline, is one of the most verifiable ways to generate a Bitcoin seed.

Prefer to save the page itself?

You can keep these instructions without a PDF by saving this page directly to your device:

  • •Desktop: Press Ctrl+S (Windows/Linux) or Cmd+S (Mac) and choose Save as Web Page (Complete).
  • •Mobile (Chrome/Safari): Open the browser menu and tap Download page or Add to Reading List for offline access.
  • •Open the saved file on an offline (air-gapped) machine whenever you need it.

Critical Warning — Read Before Using

Any seed phrase created with this tool while online must never be used for an actual wallet. The tool can and should be downloaded and run entirely offline (air-gapped) for the purpose of generating seeds that will hold real funds.

The Ian Coleman BIP39 tool is the most widely trusted open-source mnemonic converter in Bitcoin. By supplying your own physical dice rolls as entropy, you can prove to yourself that your seed phrase was generated with true randomness — not an algorithm you can't inspect.

Steps

  1. 1

    Go to iancoleman.io/bip39

  2. 2

    Scroll down and check the box labeled "Show entropy details" .

  3. 3

    A new Entropy section will appear on the page.

  4. 4

    In the Entropy section:

    • •Change the dropdown (entropy type) from the default to Dice [1-6].
    • •Paste or type your dice roll sequence into the Entropy text box (e.g. 523146261435…).
    • •Recommended: for compatibility with SeedSigner, COLDCARD, and EntropyLab, use the Base 10 [0-9] entropy type instead of Dice [1-6] — it SHA-256 hashes your dice digit string the same way those devices do, so the same rolls reproduce the same seed.
  5. 5

    Select your desired Mnemonic Length (most people choose 24 words).

  6. 6

    The tool will automatically convert the dice rolls into a BIP39 seed phrase.

Important Notes

  • Use only the digits 1–6. Spaces between numbers are usually fine but not required.
  • For a full 24-word seed you typically need 99–100 dice rolls.
  • If generating a real seed, prefer running the page offline — save via File → Save As, or download from the project's GitHub releases.
  • Never share the resulting seed phrase or the entropy you entered with anyone.

Security Reminder

Generating a seed with your own dice is excellent for verifiable randomness, but the conversion must still be done on a trusted, preferably air-gapped machine. Always verify the resulting words on a second independent tool or hardware wallet before sending funds.

Open Ian Coleman BIP39 Tool

Source: iancoleman.io/bip39 — open-source, MIT licensed

Also Try

What to Do Next

After Generating the Seed on Ian Coleman BIP39 Tool

1

Record the Critical Information (While Still Offline)

From the tool, carefully write down (or stamp on metal later):

  • •The 24-word BIP39 Mnemonic (this is your seed phrase — the most important thing)
  • •Any BIP39 Passphrase you added (the optional "25th word")
  • •The first 2–3 receiving addresses shown for your chosen derivation path (usually m/84'/0'/0' for Native Segwit)
  • •Optionally: the BIP32 Root Key (xprv) — but you normally only need the mnemonic

Do not leave the seed or entropy on the computer longer than necessary. Clear the page / close the browser after recording.

2

Verify the Seed

  • •Confirm the tool shows a valid mnemonic (no error about checksum).
  • •Note the first receiving address. You will check this matches later when you restore the wallet.
  • •Strongly recommended: verify the same seed on a second independent tool or hardware wallet before putting real funds on it.
3

Import into Sparrow Wallet

  1. 1.Open Sparrow Wallet.
  2. 2.Go to File → New Wallet.
  3. 3.Give the wallet a name and click Create.
  4. 4.On the Settings screen:
  5. ◦Policy Type: Single Signature (default)
  6. ◦Script Type: Native Segwit (P2WPKH) — this is the modern recommended choice (addresses start with bc1q…). (You can also choose Nested Segwit or Taproot if you have a specific reason.)
  7. 5.Under Keystores, click New or Imported Software Wallet.
  8. 6.Select Mnemonic Words (BIP39).
  9. 7.Choose Enter 24 Words.
  10. 8.Carefully type (or paste if you are on a trusted offline machine) your 24-word seed phrase in the correct order.
  11. 9.If you used a BIP39 passphrase, check the box and enter it carefully (it is case-sensitive).
  12. 10.Click Create Keystore.
  13. 11.Click Import Keystore.
  14. 12.Click Apply.
  15. 13.Set a strong wallet password if prompted (this encrypts the wallet file on your computer — it is not the same as the BIP39 passphrase).

Verification Step

Go to the Receive tab and check that the first address matches the one you noted from the Ian Coleman tool (for the same script type / derivation path). If it matches, the import was successful.

4

Restore on a Hardware Wallet (Recommended for Long-Term Storage)

Most hardware wallets support BIP39 seed restore:

  • •Coldcard: Use the "Import Existing" / restore seed flow and enter the 24 words (and passphrase if used).
  • •Trezor / Ledger / BitBox / Foundation Passport / Jade / etc.: During setup or recovery, choose "Restore wallet" / "Recover from seed" and enter the words.

After restoring on the hardware wallet, always verify the first receiving address matches what you recorded from the Ian Coleman tool.

Best practice: Many people generate the seed offline (as you did), then restore it directly onto a hardware wallet and never put the seed into Sparrow (or any software wallet) if the amounts are significant. Sparrow can still be used later as a watch-only wallet by importing the xpub.

5

Final Security Steps

  • •Transfer the seed to a metal backup (steel plate, Capsule, etc.) and destroy any paper notes.
  • •Test the wallet with a small amount of bitcoin first.
  • •Only after successful receive + send of a small test amount should you move larger funds.
  • •Never enter the seed phrase on an internet-connected device if it will hold meaningful funds.
  • •Consider adding a strong BIP39 passphrase for extra protection (just never lose it).

Alternative to Dice Roll

Coin Flip with 256 Coins

How to make a 24-word seed phrase with 256 coins