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Key Management

Tools for Bitcoin self-custody: sign transactions air-gapped and store your recovery phrase in steel, safe from fire and water.

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SeedSigner air-gapped Bitcoin signing device in a black case with screen, joystick and three buttons

Key Management

SeedSigner

Rated 5.0 out of 5

€59.00

Incl. VAT, plus shipping.

Two jobs: signing and backup

Self-custody means your private keys never sit with an exchange. That leaves two tasks: signing transactions without exposing the keys, and keeping a backup of the recovery phrase that survives fire and water.

Signing: SeedSigner

The SeedSigner is an open-source signing device without any network connection. Transactions go in and out as QR codes, the private keys stay offline. Hardware and software are open, so anyone can check what the device does.

Backup: Steel Seed Set

Paper burns and gets wet. With the Steel Seed Set you stamp your recovery phrase into 24 steel discs and keep them in an aluminium tube. The set comes in orange, forest green and black.

Good practice

  • Write the recovery phrase down offline only, never as a photo or in a cloud note.
  • Keep the steel backup in a different place from the signing device.
  • Test the backup: restore a wallet from it before you move larger amounts.