Ethereum Address and Format
Format of Ethereum addresses — 0x + 40 hex characters, derived from private key.
An Ethereum address is a 42-character string (0x + 40 hexadecimal characters) representing a key pair on the Ethereum network.
Address example: 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 (Vitalik's public address)
How an address is created: 1. Private key (256-bit random number) 2. ECDSA → Public key (512-bit) 3. Keccak-256 hash of public key 4. Last 20 bytes (40 hex characters) = address 5. "0x" prefix added
ERC-55 Checksum:
•Mixed upper/lowercase letters in address for error detection
•"0xd8dA" vs "0xD8DA" — difference is in checksum
•Always verify checksum before sending
EVM compatibility:
•Same address works on Ethereum, Arbitrum, Optimism, BNB Chain, Polygon
•Different networks, same key pair
•CAUTION: USDT on ETH and USDT on Tron are DIFFERENT addresses!
Bech32 addresses (Bitcoin):
•Bitcoin Native SegWit addresses start with "bc1"
•Taproot: "bc1p"
•Legacy: "1...", P2SH: "3..."