Hardware Wallet

A hardware wallet is a physical device - typically about the size of a USB stick - that stores your private key offline and signs transactions inside the device. It is the safest common way to hold crypto assets, because the key never leaves the device and never touches an internet-connected computer where malware could steal it. Ledger and Trezor are the best-known makers.

The core idea is "cold storage." When you want to move assets, your computer or phone prepares the transaction and sends it to the hardware wallet; you review the details on the device's own screen and approve with a physical button press; the device signs it internally and returns only the signature. Even if the connected machine is fully compromised, the attacker never sees the key and cannot approve a transaction without the device in hand.

This is the main upgrade over a hot (software) self-custody wallet, which keeps the key on an internet-connected device for convenience. A common setup is to use a hot wallet for small, everyday amounts and a hardware wallet for long-term or large holdings.

Setup still produces a seed phrase, generated on the device, which you back up on paper or metal. That backup is the fallback if the device is lost or broken - and it is also the thing an attacker would need, so it must be protected just as carefully.

A hardware wallet defends against remote theft, not against physical coercion or a mistyped recipient address - you still confirm every transfer yourself. For sizeable tokenized real-world asset positions held in self-custody, it is the standard way to reduce the risk of key theft.

Source: Ethereum docs (ethereum.org), as of 2026.