Thread - Nostr Hypermedia

A message to all BIP39-based wallet providers (to include signing devices): Please make it easy for users to bring their own seed words. I'm referring to assisting a user who has generated their own seed words manually to land on a final checksum valid word. Ideally, a user should be able to generate their own seed phrase offline with indifference to a checksum. Then, when a wallet they try to enter it into for the first time detects an invalid checksum, the wallet could offer to provide the associated checksum-valid final word; so that the user may update their own physical backup and reenter their entire seed phrase for checksum verification. I realize some wallets already offer some version of this "generate final word" assistance. It really seems like this should be expected as a standard now for all wallets. Also, might be best to start encouraging users to be generating their own seed words rather than relying on a wallet to tell them what their seed words will be. PS. Thank you! Your work is greatly appreciated, and probably doesn't get the full recognition that it deserves.

Replies (2)

Judge Hardcase 4 days ago

Yes. It ought to be easy enough to explain to a normie how to flip a coin 11 times (or roll dice or whatever) to randomly select each seed word from an easily available list. It's mostly useless, however, for a normie to do so until they have a wallet that can assist them with this last step - so, it's mostly useless to encourage a normie to do it.

modulo 3 days ago

You are exactly right that the seed phrase can be generated offline regardless of the checksum. The checksum is only necessary when entering into technology, and wallets should support that. There are some entropy bits necessary in the final word that need to be made, but they are few. We put this concept into the wallet we are making:

Lightning in a Jar

where you can import your seed words and final bits in the 12th word slot. Still alpha, but if you try it let us know any feedback. For interest and educational purposes, there are two particular spreadsheets that show it: 1) list your 11 or 23 words and it shows the qualifying checksum words, and; 2) list your 11 or 23 words and remaining bits, and calculates the checksum. They can be found at

Modulo Keys

Bitcoin Spreadsheets — Modulo Keys

Free offline Bitcoin tools. SHA-256, ECDSA, seed phrase generators and more — no internet required.