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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Frequently asked questions

What does this validator check?

That a Bitcoin or Ethereum address is well-formed and that its checksum is valid: Base58Check for legacy Bitcoin, Bech32 and Bech32m for SegWit and Taproot, and EIP-55 casing for Ethereum.

Does a valid address mean the funds are safe to send?

No. It only means the string is not mistyped. It does not confirm who controls the address or whether it is the one you intend to pay, so always verify the address through a trusted channel.

Is the address sent anywhere or looked up on-chain?

No. Validation is pure format and checksum math done in your browser. There are no network calls and no balance or history lookup.