/index/ /tools/ /02 address-validator

live

Address
validator.

Standard

EIP-55

checksum verified

Length

20 B

40 hex chars

Networks

EVM chains

Hashing

Local

keccak-256 in-browser

/02—ETHEREUM ADDRESS VALIDATOR

awaiting input

EIP-55

canonical

copy

lowercase

no checksum

copy

UPPERCASE

explorer paste

copy

↺ reset

▸ /inspect — multi-chain presence

Ethereum 1

—

Optimism 10

—

Arbitrum 42161

—

Base 8453

—

Polygon 137

—

BNB Chain 56

—

Avalanche 43114

—

Linea 59144

—

Scroll 534352

—

zkSync Era 324

—

Blast 81457

—

Each row calls eth_getCode on a public RPC for that chain. Contracts return bytecode; wallets (EOAs) return 0x. No wallet connection, no API key.

▸ /reference — address forms

formexamplenote

lowercase 0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48 valid; no checksum

UPPERCASE 0XA0B86991C6218B36C1D19D4A2E9EB0CE3606EB48 valid; common from explorers

EIP-55 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 case-encoded checksum

▸ /notes

EIP-55 in one sentence.

For each letter (a–f) in the lowercase address, capitalize it if the matching nibble of keccak256(addr_lower) is ≥ 8. Wallets that produce mixed-case addresses are signaling that the case has meaning — and should be checked.

Mixed case that doesn't match.

If an address is mixed-case but doesn't pass the checksum, treat it as a typo or transmission error — not a different address. The corrupted sample above shows this; we flip a single letter from the WETH checksum to demonstrate.

Same address, every chain.

All EVM chains share Ethereum's address format. The same 20-byte address can be a wallet on one chain and a contract on another. The inspection grid checks each chain's bytecode independently — useful for spotting where a contract is actually deployed.

▸ /faq

What is an EIP-55 checksum?

EIP-55 mixes the case of letters in an Ethereum address based on the keccak-256 hash of its lowercase form. Wallets can verify the case to catch typos. An all-lowercase address is technically valid but loses this protection.

Is a lowercase address invalid?

No. Ethereum addresses are case-insensitive on-chain. Lowercase, uppercase, and EIP-55 checksummed forms all reference the same account. Mixed case that does not match the checksum is suspicious — likely a typo or copy error.

How do you tell a contract from a wallet (EOA)?

Calling eth_getCode on the address returns the deployed bytecode for a contract, or 0x for an externally-owned account. We check this on each chain you enable.

Addressvalidator.

What is an EIP-55 checksum?

Is a lowercase address invalid?

How do you tell a contract from a wallet (EOA)?

Address
validator.