Pips39: Seed from dice

Pips39 turns real dice rolls into a BIP39 word list. It is meant for an old iPhone you take offline for good, and above all for understanding the method before you use it on paper. It is not a wallet. It stores nothing, derives no addresses, signs no transactions and has no network code. Nothing stays behind when you close it. THREE WAYS, SIDE BY SIDE SHA-256: Exactly 99 rolls for 24 words, 50 for 12. The digit string is hashed. Verifiable with shasum and any BIP39 tool. Coleman: Bit for bit identical to iancoleman.io/bip39. Each roll stands for a varying number of bits, which is why the roll count is not fixed. Word table: Here the app does not compute, it replaces a sheet of paper. Five dice and a coin pick one word; only the first three dice are typed in. The app shows 32 candidates and never learns which one you took. WHAT THE APP SAYS ABOUT ITSELF The first screen says not to use it for a seed that will hold real money. For that, use dice, a printed table and paper in a room without electronics. The app cannot prove a device is offline. iOS gives no app that ability. It states what it can observe and never tells you that you are safe. TRANSCRIPTION CHECK WITH ITS OWN KEYBOARD After writing the words down you type them back, and the app confirms them one position at a time. It brings its own letter keyboard, which only enables letters a BIP39 word can continue with. The system keyboard learns words, autocorrects and can be replaced, so it is no place for a seed. HELP THAT EXPLAINS INSTEAD OF REASSURING Six pages on what is behind the method: what a seed is, why the last word carries a checksum, what the roll-pattern check can and cannot do, how long an attacker would really need against 118 hidden bits, how to take the device offline, and how to build the app yourself from source. SOURCE OPEN github.com/a6k/pips39 The computing core is a Swift package with no interface and can be checked against the official BIP39 test vectors with swift test, no simulator needed. Open source means the source is auditable. It does not mean the build from the App Store is: Apple re-signs and encrypts it. If you want certainty, build it yourself. The word table method comes from Shift Crypto AG's BitBox02 dice guide, published under CC BY-SA 4.0. Pips39 is not affiliated with Shift Crypto.