What is a seed phrase?
Quick Answer
A seed phrase (or recovery phrase) is a list of 12 or 24 simple words that backs up your entire wallet. Anyone with it can restore and control your Bitcoin, so it must be written down offline and never shared or photographed.
TL;DR
12–24 words that back up your whole wallet. Anyone with them controls your coins — store offline, never share.
Key Takeaways
- 112 or 24 words that can restore your entire wallet
- 2It is the master backup of all your private keys
- 3Anyone who has it can take your Bitcoin
- 4Write it on paper/metal offline; never type or photograph it
Full Explanation
When you set up a self-custody wallet, it generates a seed phrase — usually 12 or 24 ordinary words in a specific order. Those words encode the master secret from which all your private keys are derived, which is why a single phrase can back up an entire wallet. If your phone breaks or you switch wallets, entering the seed phrase restores access to all your Bitcoin.
Because it is the master key to everything, the seed phrase is the single most important thing to protect. Anyone who sees it can recreate your wallet and steal your coins, and if you lose it with no copy, your Bitcoin is gone forever. There is no 'forgot password' reset in self-custody.
Best practices: write the words on paper or stamped metal and store them offline in a safe place, ideally with a backup copy in a second location. Never type your seed phrase into a website or app, never store it in cloud notes or photos, and never share it with anyone — no legitimate support team will ever ask for it.