Glossary
Cold wallet
A cold wallet keeps the private keys that control your crypto offline, on a hardware device or another medium never connected to the internet, which protects them from online attacks.
Also called Cold storage, Hardware wallet, Offline wallet, Paper wallet, Air-gapped wallet
See also
A cold wallet is a way of storing crypto in which the private keys stay offline. The coins are still on the blockchain, but the secret needed to move them is kept away from internet-connected computers and phones, out of reach of malware and remote hackers. It is the opposite of a hot wallet.
How a cold wallet works
The most common cold wallet is a hardware wallet: a small device with a secure chip that generates the keys and never exports them. When you want to send funds, an app on your computer or phone prepares the transaction and sends it to the device. You check the amount and address on the device screen and confirm with a button. The device signs inside the chip and returns only the signed transaction.
Other forms exist: a paper or metal backup of a seed phrase, or an “air-gapped” device that exchanges data only through QR codes or a memory card. Exchanges also use the term cold storage for the share of customer funds they keep offline.
A concrete example
Tom keeps a few hundred dollars of crypto in a phone app for daily use and moves his long-term savings to a hardware wallet. Months later, his laptop is infected with malware that tries to swap the address he pastes. When he prepares a withdrawal, the device screen shows an address he does not recognise, so he refuses the transaction. Without his physical confirmation, the malware cannot move the funds.
Why it matters for users
Cold storage is the standard advice for amounts you would hate to lose and do not need to move often. It removes the largest risk of self-custody, a compromised device. Hardware wallets range from well under $100 to a few hundred dollars.
Limits and risks
- A cold wallet is only as safe as its seed phrase backup: lose both device and backup and the funds are gone.
- It protects keys, not judgement: signing a malicious transaction or approval on the device still drains funds.
- It is slower to use, which is a feature for savings but awkward for frequent trading.
- Buy devices only from the manufacturer or an authorised reseller to avoid tampered units.
Step-by-step instructions are in our guide How to set up a hardware wallet.