How to store a seed phrase safely

Store a seed phrase offline, written by hand on paper or stamped into metal, in at least two separate safe places — never as a photo, a screenshot, a cloud note, an email or a password-manager entry on an online device. The 12 or 24 words are your wallet: anyone who reads them can take everything, from anywhere, without your device.

What a seed phrase is

Most wallets follow a standard called BIP-39: a list of 12 or 24 words drawn from a fixed list of 2,048. The words encode a large random number from which the wallet derives every private key and address it will ever use. That is why one phrase restores a whole wallet on a new device, in any compatible app, and why it needs more protection than any single key.

Writing it down

• Write it by hand, on the card that came with the wallet or on plain paper, with each word numbered. Check every word against the wallet's screen.
• Never type it into a computer or phone to "save" it, and never photograph it. Phones back photos up to the cloud without asking.
• Most wallets offer to check the backup by asking for a few words. Do it, then restore the wallet from the phrase once while it holds little, to prove the backup works.

Paper or metal

Paper is fine in a dry, safe place, but it burns, floods and fades. A metal backup — letters stamped into steel or tiles slotted into a plate — survives a house fire. For a phrase protecting serious savings, metal is worth the cost. Whichever you use, it is only as safe as where you keep it.

Where to keep it

Two copies in two places protects against one place being lost to fire, flood or theft: a home safe and a trusted relative's house, for example, or a bank safe-deposit box. More copies mean more places it can be found. Keep it separate from the hardware wallet itself, so one burglary does not get both.

The optional passphrase

Many wallets let you add a passphrase on top of the words, sometimes called the 25th word. With it, the words alone open a different, empty wallet, so a found seed phrase is not enough to take your coins. The cost is that a forgotten passphrase loses them just as surely as a lost phrase, so it needs its own backup, stored apart from the words.

What never to do

• Never enter it on a website. No exchange, tracker, airdrop or support agent needs it. A page asking for it is stealing it.
• Never give it to support. Real support teams never ask. Anyone who does — in a DM, an email, a call — is a scammer.
• Never store it in the cloud. Notes apps, email drafts, photo libraries and shared documents all sync to servers you do not control.
• Never split the words between places as a security measure. Half a phrase gives an attacker a head start. If you want a backup that survives one copy being found, look at multisig or a wallet's built-in share-based backup, which are designed for it.

Planning for someone else

If you were gone tomorrow, could your family find and use the coins? A sealed letter with instructions — where the backup is, which wallet it restores, and that nobody legitimate will ever ask for the words — stored with your will or with someone you trust, solves the problem without exposing the phrase now.

This guide explains how things work. It is not financial, investment or tax advice. Something wrong? Write to hi@perly.io and we will correct it.