Offline Signing
Preparing a transaction on a connected device and authorizing it with keys kept on a separate offline signer.
Offline signing separates transaction construction and broadcasting from access to private keys. An online watch-only wallet prepares an unsigned transaction, an offline device reviews and signs it, and the signed transaction returns to a connected device for broadcast.
Transaction data may move by QR code, removable storage, or a protocol-specific file. Both sides must agree on the network, asset, inputs, outputs, fee, and serialization format; an air gap does not correct incompatible or incomplete data.
Offline signing reduces remote key exposure but does not make the online system trustworthy. The signer must independently display and verify destination addresses, amounts, change, fees, and contract details because compromised transaction-building software can request a valid signature for the wrong payment.
Related terms
Explore connected entries beyond the alphabetical index.
Air-Gapped Wallet
→A signing setup designed to keep private keys on a device isolated from ordinary data networks.
Cold Storage
→A custody arrangement that keeps signing keys unavailable to ordinary internet-connected systems.
Watch-Only Wallet
→A wallet that monitors balances and transactions but cannot spend because it lacks the required private keys.
Signature
→A cryptographic proof that a message was authorized by the holder of a private key.