Address checksum (EIP-55): validate and format an EVM address

$0.01 per call · failed calls are never charged · no account or API key needed

Validate an EVM address and return its EIP-55 checksummed form, saying whether the input was all lower case, all upper case, correctly checksummed or mixed case with a wrong checksum (a likely typo). Works for every EVM chain. Use before sending funds or storing an address; for whether it is a contract use <chain>_is_contract.

Run it free (25 free calls) Buy credits by card (from $5) Example result (JSON)

Try it with your own inputs

0x address (40 hex characters)

Uses one of your 25 free calls. Nothing is charged, and a call that fails is not counted.

Inputs

NameTypeDescription
address (required)string0x address (40 hex characters)

Request

Over HTTP, with a card key from /credits:

curl -H "Authorization: Bearer adt_…" "https://agent-data-tools.revmesh2074.workers.dev/evm/checksum?address=0xd8da6bf26964af9d7eed9e03e53415d37aa96045"

Or one of your 25 free calls, no key:

curl "https://agent-data-tools.revmesh2074.workers.dev/evm/checksum?address=0xd8da6bf26964af9d7eed9e03e53415d37aa96045&trial=1"

Without a key, the same URL answers 402 Payment Required with x402 and MPP terms, so an agent with a wallet pays per call in USDC (Base, Polygon, Arbitrum or Solana over x402; Base or Tempo over MPP) and retries.

Example result

{
  "input": "0xd8da6bf26964af9d7eed9e03e53415d37aa96045",
  "valid": true,
  "checksummed": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
  "inputCase": "lower",
  "checksumMatches": null
}

From an AI agent (MCP)

Add the MCP server to Claude, Cursor or any MCP client. This tool is evm_checksum, and the first 25 successful calls are free:

https://agent-data-tools.revmesh2074.workers.dev/mcp

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