TL;DR: Bitcoin uses a private key, which is a lengthy 256-bit number that can be challenging to recall and input accurately. To make things easier, Bitcoin uses a recovery phrase, an ordered list of words from which the private keys are derived. Store your bitcoin safely by using a signing device to generate a recovery phrase, write the words down in the correct order on a durable material, and consider adding a password or pin for extra security. It is best to avoid using electronic devices to store or reveal the recovery phrase, as they may be vulnerable to cyber-attacks. Understanding the basics of private keys and seeds helps avoid costly mistakes.
A private key is a massive 256-bit number that is difficult to remember or input without errors. To simplify this process, Bitcoin uses a recovery phrase (also called a seed phrase), which is a list of plain English words from which your private keys are derived (details in BIP-39).
In some cases your Bitcoin wallet will offer an additional pin (like in the Blockstream app) or password (like in BlueWallet) for extra security. This protects access to the wallet app and is separate from the recovery phrase itself.
You only need to focus on the word list and the optional pin/password. Understanding the basics helps avoid mistakes that can be hard to fix, such as incorrect word order or password capitalization. It's essential to know that you need both the seed and the password.
For those less technical, you can think of the recovery phrase as your private key. Technically, it is not, but everything can be derived from the seed. Just remember that the seed words must be in the correct order!
To store your bitcoin safely, follow these steps:
- Use a reliable source of randomness (entropy) to create a secure private key. A signing device or "hardware wallet" is recommended for this purpose, as they are optimized for generating seeds. Set a PIN code or password for the device and remember it or write it down.
- When the device generates a new wallet, it will display the seed words in sequence. Write these seed words down manually on paper or, ideally, on a metal plate. Ensure you write them in the correct order and avoid using any electronic devices during this process. Never type the seed words into a computer, take photos or screenshots, or expose them to others or cameras.
- If you are confident you will not forget or misplace a passphrase, consider adding one to your seed when you login. This allows you to store the seed and passphrase separately, increasing security. With the same seed words and different passwords, you can also create separate wallets for various purposes, such as separate "accounts" for hot and cold storage or a honeypot account to protect your funds. Passwords are powerful tools, but do not lose them!
Because of its value, Bitcoin is a target for attackers. As a best practice, avoid storing your recovery phrases electronically, as malicious actors may try to access them. These safeguards are your main defense against theft.
Private key: key facts
- A Bitcoin private key is a 256-bit number that authorizes spending from an address. It is normally handled as a 12 or 24-word recovery phrase rather than the raw number.
- The public key and your receiving addresses are derived from the private key, never the other way around.
- Anyone who obtains the private key can move the funds; there is no password reset and no recovery service.
- Generate it on a signing device, record the recovery phrase offline in the correct order, and never type it into an internet-connected device.
What a Private Key Looks Like, and Why You Rarely See the Raw Form
In its raw form a private key is a 256-bit integer, usually shown as 64 hexadecimal characters. That format is impractical to copy by hand without error, so wallets follow BIP-39 and present the key as an ordered list of common English words. The words are not a separate secret sitting alongside the key; they encode the entropy the key is derived from, which is why getting a single word or its position wrong produces a different wallet. You should never need to read, type, or display the raw hexadecimal private key during normal use, and any app, site, or person asking you to enter it is a red flag.
Private Key, Public Key, and Address: How They Relate
The private key sits at the root. From it, Bitcoin derives a public key, and from the public key it derives the addresses you share to receive funds. The derivation runs one direction only: a receiving address reveals nothing that lets anyone reconstruct the private key. This is what makes it safe to post an address publicly while the private key stays secret on your signing device. Modern wallets generate a fresh address for each payment from the same underlying key, which improves privacy without creating new secrets to back up.
Frequently Asked Questions
How do I get my private key?
A self-custodial wallet generates the private key for you and represents it as a recovery phrase shown once during setup. Write those words down then; that is your private key in usable form. Wallets deliberately avoid exposing the raw key, and a hardware wallet such as Blockstream Jade keeps it on the device so it never touches an internet-connected computer.
What does a private key look like?
Internally it is a 256-bit number, commonly displayed as 64 hexadecimal characters. In practice you interact with it as a 12 or 24-word recovery phrase, because the word list is far easier to record accurately and to verify. Both represent the same secret; the words simply encode it in a human-readable form.
What happens if someone gets access to my private key?
They can spend every coin it controls, immediately and irreversibly, without needing anything else from you. Bitcoin has no central authority to freeze or reverse the transaction. This is why the private key must never be photographed, typed into a website, stored in the cloud, or shared, and why an offline backup is the only safe place for it.
Is a recovery phrase the same as a private key?
For practical purposes, yes. Technically the phrase is the seed from which the wallet derives the private keys, but anyone holding the words can recreate the wallet and all of its keys. Treat the recovery phrase with exactly the same care you would the private key itself, because controlling one means controlling the other.
Can a private key be recovered if I lose it?
No. If the private key and its recovery phrase are both gone, the associated bitcoin is permanently unspendable, and no service can restore it. The safeguard is redundancy: keep more than one durable backup of the recovery phrase in separate physical locations, ideally stamped into metal rather than written on paper.