Address starting with “1”

Coin: Bitcoin (BTC)
Type: Legacy pay-to-public-key-hash (P2PKH), Base58Check with version byte 0x00
Length: 26–34 characters
Confused with: Bitcoin Cash and Bitcoin SV legacy addresses look exactly the same. A 1… address on its own cannot say whether BTC or BCH is meant. Polkadot accounts also start with 1, but have 47–48 characters.

The oldest address type. Every wallet and exchange accepts it; transactions from it cost more than from bc1 addresses because the signature data is larger.

Check one

Checked in this browser. The address is not sent to a server.

Public examples

Valid format and checksumBitcoin · Legacy · P2PKH

Base58Check checksum matches

Parts of this address

1Prefix 1
Fixed by the version byte 0x00 → Bitcoin pay-to-public-key-hash.
2Payload A1zP1…Lmv7
20-byte hash of the public key: 62e907b1…8f18.
3Checksum DivfNa
Last 4 bytes, taken from a double SHA-256 of everything before. Base58 does not align to bytes, so the marked characters are approximate.

Details

Network: Bitcoin
Type: Legacy · P2PKH
Encoding: Base58Check
Length: 34 characters · 25 bytes
Checksum: matches
Version: 0x00
Hash: 62e907b15c…

Watch out

Bitcoin Cash legacy addresses look the same (1… and 3…). Make sure the sender is sending BTC, not BCH.

Same address in another form

If this is a Bitcoin Cash legacy address, its CashAddr formbitcoincash:qp3wjpa3tjlj042z2wv7hahsldgwhwy0rq9sywjpyy

What this does not proveA valid format only means the address is well-formed. It does not show who controls it or that it is the address the recipient gave. Compare the whole address with the source and send a small test amount first.

FAQ

What coin uses addresses starting with 1?

Bitcoin (BTC). Legacy pay-to-public-key-hash (P2PKH), Base58Check with version byte 0x00.

What can a 1 address be confused with?

Bitcoin Cash and Bitcoin SV legacy addresses look exactly the same. A 1… address on its own cannot say whether BTC or BCH is meant. Polkadot accounts also start with 1, but have 47–48 characters.