Batch address
checksum.

Parsed

addresses in the list

Protected

checksum verified

Problems

invalid or failed checksum

Network

None

keccak runs locally

/26—EIP-55 BATCH CHECKER

▸ /notes

One bit per letter.

EIP-55 hides a keccak-256 checksum in the casing of each hex letter, so a valid mixed-case address is self-verifying text. The full explainer walks through the algorithm; this tool just runs it a few hundred times at once.

Where lists go wrong.

Spreadsheets lowercase addresses, chat apps truncate them, and copy-paste drops characters. A batch pass catches all three: wrong shapes are flagged, failed checksums are called out, and everything valid comes back in canonical form.

Checking a single address?

The address checker goes deeper on one address: checksum, canonical forms, and contract-versus-wallet detection across 11 EVM chains.

▸ /faq

What does the batch checker flag?

Three things per address: a wrong shape (not 40 hex characters), a mixed-case address whose casing fails the EIP-55 checksum (almost certainly a typo), and case-uniform addresses that are valid but carry no checksum protection. Everything valid is re-emitted in canonical EIP-55 form.

Is it safe to paste a large address list here?

The list never leaves your browser: shape checks, keccak hashing, and checksum casing all run locally, and this page makes no network requests. Addresses are public information, but local processing means you do not have to take our word for it.

What separators can I use?

Newlines, spaces, commas, and semicolons all work, in any mix. Exports from spreadsheets, block explorers, or code paste in directly.

Why normalize to EIP-55 at all?

A checksummed list is self-verifying: any later transcription error is detectable from the text alone. If you maintain allowlists, config files, or docs, storing the EIP-55 form catches corruption for free.

Batch addresschecksum.