Addresses

If the seed is the secret you guard with your life, an address is its opposite — the thing you hand out. It’s how people send you Bitcoin, and it’s completely safe to share with the world.

Where an address comes from

An address is derived from a public key, which in turn comes from your private key through the elliptic-curve maths from the Cryptography section — a strict one-way street. Publishing your address therefore reveals nothing about your keys and puts nothing at risk. Your wallet can generate an effectively unlimited number of addresses, all flowing from that same single seed.

See it derived, byte by byte

Here’s the real derivation — the exact steps your wallet runs. Type a key or hit Random, then switch the address type to watch the same key become a Legacy “1…”, Nested SegWit “3…”, Native SegWit “bc1q…” or Taproot “bc1p…” address. Every arrow is a one-way function, so the address gives nothing away; the checksum at the end is what lets wallets catch a mistyped address before your coins go astray.

Private key (hex — the secret) Address type

Use a fresh one each time

The best practice is a brand-new address for every payment you receive. Because the blockchain is fully public, reusing one address lets anyone tie all the payments to it together — and to you. Rotating addresses, which your wallet does automatically, keeps your financial life much harder to piece together from the outside. An old address still works forever; you simply gain privacy by not leaning on any one of them.

The formats you’ll see

You’ll come across a few styles: older addresses beginning with 1 or 3, and modern “bech32” addresses beginning with bc1, which are cheaper to spend from and better at catching typos before your coins go astray. You don’t need to memorise the differences — your wallet handles them. You just copy the address and share it.

One habit worth building early: before receiving or sending anything large, confirm the address character-for-character on your hardware wallet’s own screen. Malware’s favourite trick is silently swapping a copied address for the attacker’s — the maths can’t save you from pasting the wrong destination.

You now have a seed to guard and addresses to share. The next question is a physical one: where should your keys actually live — hot, cold, or somewhere in between?

Key takeaways

An address is derived from your public key and is safe to share — it’s how people pay you.
Use a fresh address for each payment for privacy, since the public ledger links reused addresses together.