BUILD YOUR OWN
BITCOIN SIGNING DEVICE
using a raspberry pi zero (VERSION 1.3)
You can build an offline, air-gapped Bitcoin transaction signing device from off-the-shelf components for less than $50!
The fastest and easiest way to run the latest version of SeedSigner is to download our most recent release.
Want to maximize your signer’s trustlessness? Check out our manual build instructions to build from the source code.
The SeedSigner is project is focused on lowering the cost and complexity of creating and using Bitcoin multi-signature wallets. With a single SeedSigner device, you can manage an infinite number of multi-signature cosigners for an infinite number of multisig wallets. And because SeedSigner doesn’t store seed phrases or private key data after it has been powered off, different parties can even use the same device to manage their long-term Bitcoin savings.
Use SeedSigner to complete these tasks:
- Calculate the final word of 12/24 word seed phrases
- Generate a 24 word seed phrase from 99 dice rolls
- Generate a 24 word seed phrase using entropy from a digital photo
- View extended public key info to verify XPUBs provided by other wallets
- Export extended public keys for use during initial wallet setup
- Create a Seed QR code to quickly & easily input your seed for signing
- Add a BIP39 passphrase to your seed phrase for additional security
- Use air-gapped QR exchange to securely sign transactions
The key component in SeedSigner is a specific version of the Raspberry Pi Zero single board computer (version 1.3) that does not include WiFi or Bluetooth functionality; the absence of these modules ensures that your private keys never leave the device. Communication with wallet software is accomplished using a two-way QR code exchange process. Information about a proposed transaction is displayed by the wallet software on your computer’s screen, encoded in multiple QR codes, and you scan in the transaction information using SeedSigner’s built-in camera. Information about the proposed transaction is then displayed on the SeedSigner screen. Using cryptographic signatures, SeedSigner then proves that it has the correct private keys to authorize the transaction, and QR codes demonstrating that proof are displayed on SeedSigner’s screen. You then use your computers web-camera to input the QR codes generated by SeedSigner to authorize the transaction.
SeedSigner is built to be compatible with Specter-Desktop, Sparrow Wallet and BlueWallet Multisig Vaults.
Visit our SeedSigner Telegram community for support and feedback
What people are saying about SeedSigner?
The information below were all from Twitter
The @seedsigner + @bluewalletio stack is highly underrated.— ODELL (@ODELL) September 18, 2021
Nearly four billion people have a smartphone. For ~$50 they can build a seedsigner and easily use it with their existing smartphone. Cheap and accessible access to relatively secure bitcoin storage. Not priced in. https://t.co/AXOIrGNtzI
9/ 25 million satoshis to @SeedSigner for their work creating inexpensive open-source hardware wallets to enable people to be their own bank for as little as $50. Encouraging open-source self-custody in difficult political environments is a priority for HRF moving forward.— Alex Gladstein 🌋 ⚡ (@gladstein) September 14, 2021
Inspiring kids to become sovereign #Bitcoin badasses just had a major ⬇️ difficulty adjustment.— MICROCHAD does not comply (@mtcbtc) September 6, 2021
3D printed goodness courtesy of @surfacePlasmon @openoms @ https://t.co/Q0ljdRYZBj and @blackcoffeebtc @ https://t.co/KGrJhYwt9l securing self-built, air-gapped @SeedSigner ✌️😎🔥 pic.twitter.com/W8wP3QYfgm
SeedSigner Development Fund
Please consider making a donation to our development fund — it is jointly managed by 5 key stakeholders in the SeedSigner project and earmarked to support the work of our developers!
BTC Address: bc1qphlyv2dde290tqdlnk8uswztnshw3x9rjurexqqhksvu7vdevhtsuw4efe