Ethereum Address Validation

Check an Ethereum address: the 0x format and the EIP-55 checksum that catches one-character typos. Returns the checksummed form.

Free to try Pay by wallet (x402) eth-address-validate

Example

Input

{
  "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"
}

Answer

{
  "input": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
  "valid": true,
  "normalized": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
  "format_valid": true,
  "checksum_valid": true,
  "is_zero_address": false,
  "checksum_present": true
}

Try it

Runs the real tool from your browser, with no key. Free calls are limited to 300 a month across all free tools.

Inputs (JSON)

{
  "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"
}

Edit the values, then run.

Inputs

Field	Type	Required	What it is
`address`	string	Yes	Ethereum address (e.g. 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045)

Output fields

How reliably each field appears in a successful answer.

Field	Type	Appears
`input`	string	Always (present in every successful answer)
`valid`	boolean	Always (present in every successful answer)
`normalized`	string or null	Usually (present for most inputs)
`format_valid`	boolean	Always (present in every successful answer)
`checksum_valid`	boolean or null	Usually (present for most inputs)
`is_zero_address`	boolean	Always (present in every successful answer)
`checksum_present`	boolean	Always (present in every successful answer)

How to call it

The same tool through each route. MCP clients reach it through Strale’s server at https://api.strale.io/mcp; the call below is what the agent sends.

# Free tool: works without a key, within a monthly allowance. Add your key for more.
curl -X POST https://api.strale.io/v1/do \
  -H 'Content-Type: application/json' \
  -d '{
    "capability_slug": "eth-address-validate",
    "inputs": {
      "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"
    },
    "max_price_cents": 5
  }'

{
  "tool": "strale_execute",
  "arguments": {
    "slug": "eth-address-validate",
    "inputs": {
      "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"
    },
    "max_price_cents": 5
  }
}

import { Strale } from "straleio";

const strale = new Strale({ apiKey: process.env.STRALE_API_KEY! });
const result = await strale.do({
  capability_slug: "eth-address-validate",
  inputs: {
    "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"
  },
  max_price_cents: 5,
});

import os
from straleio import Strale, DoRequest

strale = Strale(api_key=os.environ["STRALE_API_KEY"])
result = strale.do(DoRequest(
    capability_slug="eth-address-validate",
    inputs={
        "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
    },
    max_price_cents=5,
))

# No account. The first request answers 402 with the price in USDC;
# an x402 client pays it from your wallet and repeats the request.
curl -i -X POST https://api.strale.io/x402/v2/eth-address-validate \
  -H 'Content-Type: application/json' \
  -d '{
    "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"
  }'

Limitations

Format and checksum only — no on-chain check
Validates Ethereum address format (0x + 40 hex) and EIP-55 mixed-case checksum. Does not check whether the address has a balance, has been used on-chain, or whether it's a contract or an externally owned account.
What to do instead: Use wallet-balance-lookup, wallet-age-check, or wallet-transactions-lookup for on-chain verification.
Single-case addresses skip checksum verification
EIP-55 typo detection requires mixed-case input. All-lowercase or all-uppercase addresses are accepted as format-valid (checksum_present=false, checksum_valid=null) but no typo-detection runs against them.
What to do instead: Pass the checksummed address in `normalized` to downstream calls to preserve typo detection.