JSON formatter & validator
Format, beautify, validate, and minify JSON online. Pinpoint syntax errors by line and column, sort keys, and copy or download the result.
Ethereum address checksum
Validate Ethereum addresses and convert them to EIP-55 checksum format. Spot typos in bulk lists.
How to use Ethereum address checksum
Validate an Ethereum address and convert it to the EIP-55 checksum format. Paste one address or many (one per line) to see whether each is valid, all-lowercase, or has a wrong checksum — a likely typo.
Uses Keccak-256 hashing in your browser. Works for any EVM chain address (Ethereum, Polygon, Arbitrum, Base, BNB Chain…).
Ethereum address checksum FAQs
Is Ethereum address checksum free?
Ethereum address checksum is a free online tool on ReallyUseful.Tools. No account is required.
Does Ethereum address checksum run in my browser?
Ethereum address checksum is designed to run in your browser where supported, so files can stay on your device instead of being uploaded to a server.
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