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What is a hardware wallet?
A hardware wallet is a small physical device that stores private keys offline and signs transactions inside the device. The computer or phone it connects to sends the transaction to the network but never sees the keys.
What it means for you
The device protects keys from malware on your computer, but it will still sign whatever you approve, so read the amount and address on its own screen. If the device breaks or is lost, the seed phrase backup is what restores the funds. Buy it from the maker, not a used one.
How it works
The device creates and keeps the private keys, and no other software can be installed on it. To spend, the wallet app on a networked computer or phone fills in the transaction and sends the details to the device; you review them on the device's own screen, sometimes entering a PIN or passphrase, and the device signs and returns the signed transaction for the app to broadcast. The keys never leave the device, so malware on the computer cannot copy them, though it can try to get a different transaction in front of you to approve.
Sources: ethereum.org: Ethereum wallets, bitcoin.org: Secure your wallet, Bitcoin developer guide: Wallets · checked 4 October 2026
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Educational content, not financial advice. Written by hand and checked against the source named above. Something wrong? Tell us and we reply within two business days.