Keys and addresses
Private keys, public keys, addresses, seed phrases and HD wallets.
Private keys
A private key is a secret 256-bit number that controls your bitcoin. Learn what it looks like, how it creates addresses and how to keep it safe.
Public keys
A public key is a point on the secp256k1 curve, calculated from your private key. Learn its formats, how it becomes an address and when it is revealed.
Bitcoin addresses
A Bitcoin address is a short code that tells a sender how to lock coins to you. It is not an account and holds no balance by itself. Learn how it works.
Bitcoin address types compared
Compare Bitcoin address types: Legacy (1…), P2SH (3…), native SegWit (bc1q…) and Taproot (bc1p…). See costs, compatibility and which to use.
Base58Check encoding
Base58Check writes data using 58 easy-to-read characters plus a 4-byte checksum that catches typos. Learn how legacy addresses and WIF keys are built.
Bech32 and Bech32m
bc1 addresses use Bech32 (SegWit v0) or Bech32m (Taproot and later). They are lowercase, QR-friendly and catch typos. Learn how they are built.
Seed phrases (BIP 39)
A seed phrase is 12 or 24 words that encode the randomness behind every key in your wallet. Learn how it works, and how to store it safely.
HD wallets (BIP 32)
A hierarchical deterministic (HD) wallet derives an endless tree of keys from one seed, so a single backup restores everything. Learn how it works.
Derivation paths
A derivation path like m/84'/0'/0'/0/0 says exactly where a key sits in an HD wallet. Learn how to read one and fix a restore that shows zero balance.
Extended public keys (xpub)
An xpub can generate every receiving address of a wallet account without being able to spend. Learn its uses and why you should keep it private.
WIF private key format
WIF writes a single Bitcoin private key in Base58Check so it can be copied between wallets. Learn the format, the prefixes 5, K and L, and how to sweep.
Output descriptors: a wallet’s script blueprint
Learn how Bitcoin output descriptors combine keys, derivation paths and script types, and why recovering keys alone may not recover a wallet.
Descriptor checksums: detect errors, not ownership
Understand Bitcoin descriptor checksums, what they protect during backup and import, and why a valid checksum cannot authenticate a wallet policy.