SeedSigner

What is SeedSigner?

SeedSigner is a Bitcoin signing device you build yourself from off-the-shelf parts: a Raspberry Pi Zero (version 1.3 without Wi-Fi or Bluetooth is recommended), a 1.3-inch display with buttons, a camera and a microSD card.^[1],[2] The software is released under the MIT licence, and the case design is open too, so you can 3D-print it yourself.^[1],[3]

The project’s goal is to make multisigGlossaryMultisig (multi-signature)A wallet in which several keys jointly control the bitcoin – for example 2 of 3. If one key is lost or stolen, the bitcoin stays safe. In return, setting it up and backing it up is considerably more demanding.On the learning path: Stage 6 · Step 4 – Inheritance & emergency plan →In the glossary →× cheaper and simpler.^[1] SeedSigner works with wallet software such as SparrowProvider · Software walletSparrow WalletBitcoin desktop wallet with no purchase price and full transparency: coin control, PSBT, multisig and support for most hardware wallets.Non-custodial software – no financial licence required · reviewed Sept 2026Price: no purchase price (donations welcome); network fee when sending (as of Sept 2026)On the learning path: Stage 5 · Step 2 – Setting up your first wallet →Our profile →Official website ↗×, NunchukProvider · Software walletNunchukMultisig wallet for smartphone and desktop – no subscription if you do it yourself, subscriptions for assisted multisig and inheritance.Non-custodial software – no financial licence required · reviewed Sept 2026Price: Basic version $0; subscriptions $120 to $2,100 a year (as of Sept 2026)On the learning path: Stage 5 · Step 2 – Setting up your first wallet →Our profile →Official website ↗×, BlueWalletProvider · Software walletBlueWalletOpen-source wallet with no purchase price for iPhone, Android and Mac – Bitcoin only, with multisig, watch-only and hardware wallet support.Non-custodial software – no financial licence required · reviewed Sept 2026Price: no purchase price; network fee when sending (as of Sept 2026)On the learning path: Stage 5 · Step 2 – Setting up your first wallet →Our profile →Official website ↗×, Keeper, Specter and Bull Wallet. These show your balance and prepare transactions; SeedSigner signs them.^[1] How multisig works: Multisig simply explained.

Costs (as of September 2026)

The software has no purchase price; according to the project, the parts usually cost under $50.^[1] The project deliberately links to general electronics retailers rather than Bitcoin shops: this lowers the risk of tampered deliveries and of your details ending up on a list of Bitcoin customers. Kits and assembled devices are sold by third parties; there are no official vendors.^[2]

How it works

• Stateless: SeedSigner does not store keys permanently; switching it off clears the memory.^[1],[3] Each time you use it, you load your seed phraseGlossarySeed phrase (recovery phrase)A sequence of usually 12 or 24 words from which your wallet derives all its private keys. Anyone who knows the words has full access to your bitcoin – so they belong in an offline backup and never in anyone else’s hands.On the learning path: Stage 5 · Step 3 – Backing up your seed phrase →In the glossary →× again, by typing it in or as a SeedQR – a QR code that contains the seed words.^[3]
• QR codes only (air gapGlossaryAir gapAn air-gapped signing device has no cable or wireless connection to other devices. Transactions travel back and forth by QR code or memory card – so the private key stays completely offline.On the learning path: Stage 6 · Step 1 – Hardware wallets compared →In the glossary →×): the wallet on your computer or phone shows the unsigned transaction (PSBTGlossaryPSBT (partially signed Bitcoin transaction)A standard format for Bitcoin transactions that are not yet fully signed. It lets a wallet app, a hardware wallet and co-signers pass a payment between them without sharing private keys.On the learning path: Stage 6 · Step 1 – Hardware wallets compared →In the glossary →×) as a QR code. SeedSigner reads it with its camera, displays it for you to check, signs it and returns the result as a QR code.^[1]
• Creating a seed: with dice rolls or a camera photo as the source of randomness.^[3]
• Verifiable: since version 0.7.0 the software images have been reproducible – anyone can rebuild them from the source code and check that they match byte for byte.^[4]

What to watch out for

• Your backup is everything. A SeedQR is as valuable as the seed words themselves – store it just as securely. The device has no secure elementGlossarySecure element (security chip)A chip specially hardened against physical attacks, like the ones in bank cards and passports. In many hardware wallets it protects the PIN and secrets if the device falls into the wrong hands.On the learning path: Stage 6 · Step 1 – Hardware wallets compared →In the glossary →×. More on this: Backing up your seed phrase.
• Verify the software: download it only from the official GitHub repository and check the signature as the instructions describe.^[3] Reputable sellers ship devices without preinstalled software.^[2]

If you are just starting out, a ready-made device with manufacturer support is usually easier: Hardware wallets compared.