Bitcoin & Ethereum Address Validator

Validate the format and checksum of Bitcoin (P2PKH, P2SH, SegWit, Taproot) and Ethereum (EIP-55) addresses — entirely in your browser.

Privacy: All processing happens in your browser. Your input is never sent to our servers. This tool validates address format and checksum only — no network calls, no balance lookups.

Try these examples:

Bitcoin Address Formats

Bitcoin has evolved through several address formats, each with different security and efficiency characteristics:

Ethereum Address Checksum (EIP-55)

Ethereum addresses are 20 bytes (40 hex characters) prefixed with 0x. The EIP-55 standard introduces mixed-case checksums: certain letters in the address are capitalised based on the Keccak-256 hash of the lowercase address. This allows wallets and tools to detect typos without changing the underlying bytes.

An all-lowercase or all-uppercase Ethereum address is technically valid but non-checksummed. This tool will report the correct checksummed form if the provided address isn't already checksummed.

Why Validate an Address?

Sending cryptocurrency to an invalid address results in a permanent, irreversible loss of funds. Address validation catches common mistakes: typos, wrong network (mainnet vs testnet), incorrect format, or a failed copy-paste. Always validate before sending — especially large amounts.

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