Public vs Private Keys

What are Private Keys?

A private key (sometimes called an extended private key) is a 64-digit string of letters and numbers, which allows you to control your bitcoin wallet.

What is a Passphrase?

Because this 64-digit random string is nearly impossible to memorize, and a hassle to store, your wallet app has turned it into a 12-word passphrase, also known as a seed phrase, mnemonic seed, recovery phrase, backup phrase and several other combinations of those words.

What is a Seed Extension?

Some digital wallet apps allow you to create your own password to encrypt your seed phrase and make it harder to access. This will essentially require a 13th word to be added to the generated passphrase. It’s not advisable to store this additional word with the original 12, because the idea is to make your money harder to steal. Ideally, this would be a word that you just know, memorize, and manually add to the 12-word passphrase when importing your wallet.

How do I Save my Passphrase?

There are a few ways to save it securely, but many people recommend writing it down, old school, word by word, and keeping that paper somewhere safe. You might even want to make multiple copies. But make sure only you have access to these, because anyone can import your wallet and steal your bitcoin if they have the seed phrase. (Also make sure not to store the paper somewhere that it could become wet, catch on fire, or otherwise get destroyed.)

Public vs Private Keys

A public key, or public address, is usually 34 digits long, and also looks like a random string of letters and numbers (because, well, that’s exactly what it is!)



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