Paper Wallets Explained: Cold-Storage Keys on Paper

A paper wallet is a private key printed or written on paper, usually as a WIF string, a hex key, or QR codes for the address and key. Because the key never touches a computer, it is a form of cold storage.

How to use one safely

• Create it on a trusted, offline device and never photograph or scan it with a connected phone.
• Keep it dry, away from heat and light: paper degrades.
• When you want to spend, sweep the full balance: import the key into a software or hardware wallet and move the funds to a fresh wallet. Do not keep spending piecemeal from paper; the key has been exposed the moment it touched a device.

BIP-38 encrypted paper wallets

Some paper wallets encrypt the key with a passphrase (BIP-38). Without the passphrase, the encrypted key cannot be imported - the same password-search problem as an encrypted wallet file, worked through below.

What a paper wallet does not give

A paper wallet with only a public address shows you the balance on a block explorer but cannot restore anything. Access requires the private key or its decrypted form.

If you find an old paper wallet, check the address on a block explorer first; the balance tells you whether the key is worth sweeping at all.

What can go wrong with a paper wallet

A paper wallet is a printed private key, whether as a QR code, a hex string, or a BIP-38 encrypted key. It is only as safe as the way it was created: it should be generated offline, printed on a printer that is not connected to the internet, and stored somewhere only you control.

The problems people actually have

• Damaged prints: faded ink, torn paper and lost scans are the common failures. High-resolution scans from multiple angles preserve what is readable, and QR error correction can survive partial damage.
• Forgotten BIP-38 passphrase: the printed key is encrypted; the passphrase is the lock. A remembered length or character pattern narrows which combinations are worth testing against the printed key; with nothing remembered at all, every combination has to be tried.
• Sweeping, not sending: the correct way to empty a paper wallet is to sweep the key into a fresh wallet, never to send from the paper address repeatedly.
• A printed address that does not match: if the derived address differs from the printed one, the key was mis-typed or the print is wrong; check before moving anything.

Once the key is imported and verified, move the funds to a wallet with a properly backed-up recovery phrase and retire the paper - reusing it defeats the point of a one-time key.