Reading Bitcoin addresses and payment QR codes

A Bitcoin address is a user-facing encoding related to a locking script. Modern formats improve error detection and efficiency, but compatibility varies across older services. <strong>Networks must match.</strong> Mainnet, testnet and other networks use distinguishable formats, yet users should still confirm the selected network. Sending another asset or using an incompatible chain can make recovery difficult or impossible.

<strong>Fresh addresses improve privacy.</strong> Reusing an address makes it easier to associate payments and balances. Hierarchical deterministic wallets generate many receive addresses from one backed-up seed, so freshness does not require a new backup every time.

An address beginning with bc1 usually signals a modern Bitcoin mainnet format, while older formats often begin with 1 or 3. That visual check can catch an obvious mismatch, but it is not enough. Let the wallet validate the checksum and network, then verify the full destination on a trusted display.

Do not manually edit a character or assume that a similar-looking prefix proves the address belongs to the intended recipient. For repeated receipts, provide a fresh address each time. The wallet can derive it from the same backed-up seed, so using a new address does not require a new recovery phrase.

Address freshness reduces simple public linkage, while reusing one donation or invoice address exposes its complete incoming history and current unspent outputs to anyone who looks.

An address is a public key hash or a script hash, plus a version prefix, plus a checksum, encoded so it can be copied by hand. Legacy addresses use Base58Check, whose four-byte checksum catches almost all typos.

SegWit addresses use Bech32, an encoding designed so that any single error and most combinations of errors are detected, with a character set that avoids ambiguous letters and works in QR codes at a smaller size. Taproot uses Bech32m, a small correction to Bech32. A wallet that rejects an address is nearly always right; a wallet that accepts one only confirms it is well formed.

Addresses starting with 1 are pay-to-public-key-hash, the original format, still valid, with the largest inputs. Those starting with 3 are pay-to-script-hash: the script can be a multisig or, commonly, a wrapped SegWit script that lets older senders pay a SegWit user. bc1q addresses are native SegWit, either a key hash of 42 characters or a script hash of 62.

bc1p addresses are Taproot, 62 characters, introduced in late 2021. All four coexist and any wallet can send to any of them, though a few older services still cannot send to bc1p.

An address is not an account. Wallets generate a new one for every payment you receive, all from the same seed, precisely so that your incoming payments cannot be trivially linked on the public ledger.

Reusing an address does not risk the coins, but it ties everything sent to it together and, if the address is ever connected to your name, connects all of it to you.

Give each counterparty a fresh address, avoid posting a single 'donations' address anywhere permanent, and let the wallet manage the rest; the Bitcoin privacy guide covers what the ledger reveals beyond addresses. The address checker on this site identifies type and network without touching the chain.