What is a private key? Share your address, never your key
Short answer
A private key is a long string of characters that proves the coins at an address are yours and approves every transfer out. Your address is safe to share so people can pay you. Your private key isn't: whoever gets it can move everything at that address.
- Receiving crypto only ever takes your address, never your private key.
- A seed phrase can recreate your private keys, so guard both the same way and never share either.
- On an exchange, the exchange holds the keys. Withdraw to your own wallet and they're yours to look after.
In one line
A private key is the password to a crypto address: whoever has it can move the coins at that address.
An example
A friend wants to send you some USDT.
- You send them your address: a public string for receiving crypto, like a bank account number.
- Your private key is more like your card’s PIN. It stays in your wallet and approves transfers out. Anyone who says they need your private key to send you money is a scammer.
Related
FAQ
How are private keys and seed phrases related?
A seed phrase can recreate the private key for every address in a wallet. Keep it the same way: on paper, somewhere safe, and never share it.
Is it safe to share my address?
Yes. It works like an account number: people can send you crypto, but they can't take any. Addresses are public, though, so anyone can see an address's balance and transfers on the blockchain.
Do I have a private key for crypto I bought on an exchange?
No. The exchange holds your crypto and the keys for it, and you protect your account with a password and two-factor authentication (2FA). Once you withdraw to your own wallet, the keys are in your hands.