Chapter 1 · Not your keys, not your coins

Carry your seed phrase across any border.

Turn each of your BIP39 words into a number from a public cipher. On paper it reads like a receipt. Only you know it’s a wallet.

Pick a cipher Read the procedure

Fig. 1 · Hardware store receipt

Wood screws: $58.50
Pipe, 54.32 cm: $6.19
Gravel, 5,446 lbs: $41.00
Anchor bolts: $545.20
4 items: a seed phrase

1.1

Objective: self-custody

Your keys, offline in cold storage, answerable to no exchange and no platform that can be hacked. That’s autonomy, liberty and privacy, and it asks for vigilance.

1.2

Threat: plain words

Twelve to twenty-four words in memory fail under duress, and your family can’t inherit them. Written down, they aren’t safe in your safe or a safety deposit box: one look from an agent, a thief or a brother-in-law and the coins are gone.

1.3

Countermeasure: noise

Record numbers, not words. In the Red Crowded Ape cipher (2 January 1770), 5850 is “adjust”. Anywhere else it’s a price, a weight or a length: 5,850 · $58.50 · 5,850 lbs · 58.50 cm.

Procedure

Time required: 15 minutes · Tools: pencil, paper

Select a cipher.
Head to the ciphers and pick one by date, or by name: Color, Adjective, Animal (for example, Red Crowded Ape). Ours are spread around the internet, so you never carry the cipher across a border or keep it in the house. Download several tomes, more than you need, and pick yours offline. Remember the name, not the cipher.
Encode each word.
Open the .encode file. It’s alphabetical, so your word is quick to find. Write down its number.
Disguise the list.
Prices, weights, part numbers. The disguise is what protects you: the ciphers are public, so a list someone recognizes as a seed phrase can be tried against every one of them. Protect the wallet itself with a passphrase (see the warning below).
Recover.
Open the .decode file. It’s in numerical order: look up each number and read your words back.

Ready to start? I’ve Got My Seed Phrase walks you through it.

Warning

We will never ask for your private keys or passphrase. Never type a seed word into this site or any of its tools.

Self-custody means you are the ultimate decider of what is safe and reasonable. Use everything here at your own risk; we are not responsible for lost keys or seed words. Like the pirate rules, these are mere suggestions. Every tome is signed: verify it against the public signing key.

The ciphers hide your words. They don’t encrypt them. There are 9,132 public ciphers, every number falls between 5432 and 7479, and a seed phrase carries its own checksum, so anyone who suspects your list can test every cipher in minutes. Add a BIP39 passphrase (the “25th word”) to your wallet and keep it somewhere else, or in your head. Then the numbers alone open nothing.

Appendix A: the vault

Five signed tomes with a cipher for every day, 1770–1784 and 2000–2009, to read online or download as zips and torrents.

Open the vault

Appendix B: help out

Please download and seed our torrent files. Want to mirror some files, or have an idea? Denny at bitcoin seed book dot com.

Get the torrents

Appendix C: resources

Ways to store, transport and recover seed words, from ciphers and steganography to cold storage.

Read the resources

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