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An address that almost matches

Two different checks. One is about an address that looks like another. The other is about a character mistyped. This page does not say which wallet to use.

The coin, the network and the address, as three separate things, are on Coin, network, address.

Information, not advice.

The first characters and the last

ERC-8117 is a draft. It says wallets often show an address cut short, and that a person then checks the first characters and the last.

In the draft's example, the first four characters match and the last four match. The draft says the 32 characters between them are different. It says a transfer of no value, sent from the lookalike, can place that address in the history a person later copies.

The draft does not change the address. It proposes a way of showing one. This page does not use that way of showing an address.

Technical detail

Status: Draft. Created 30 Dec 2025. The citation is no. 8117, Dec 2025. The draft also requires EIP-1191, which was not opened. The draft calls this address poisoning. Its figures for losses, and its table of how long an address with many leading zeros would take to imitate, are not repeated.

The example addresses in the draft are 0xd28bE19170C22Bf3a5eD2E46890C9F394e3c6922 and 0xd28ba7F38c1D5e9B3f2A6c8E0d7b1F4a9C3e6922. The draft's four-step account of how a lookalike is placed in a history is not set out here as a method.

Capitals as a check on a mistype

ERC-55 is a finished standard. It keeps an Ethereum address at 40 characters and uses capitals and small letters as a check.

The standard says that, on average, there are 15 check bits, and that the chance a randomly generated address which has been mistyped still passes the check is 0.0247%. That figure is the standard's own. It is about a mistype.

The draft above says its own way of showing an address is compatible with this check. This page does not treat the check as a comparison with an address used before.

Technical detail

Status: Final. Created 14 Jan 2016. Authors Vitalik Buterin and Alex Van de Sande. The citation is no. 55, Jan 2016. The standard says the check is backwards compatible with many programs that accept mixed-case hex. The code samples are not copied.

In the standard's own words: if a character is a letter, print it in capitals when the matching bit of the hash of the lowercase address is 1, and in small letters otherwise. Digits are left as they are.