An address, explained
Paste an address and choose its chain: Ethereum, BNB Smart Chain, Base or Arbitrum One. You'll see whether it has code, how much of the chain's coin the node says it holds, and how many transactions have been sent from it. When it has code, the token check's reading of that code follows. Nothing you paste is stored.
The address is also compared with a copy of the UK Sanctions List saved from the file of 30 Oct 2026, read on 31 Oct 2026. That comparison stays on this site's server.
A Bitcoin address is not read here. Bitcoin addresses are a different shape, and this page asks the four chains that run the Ethereum virtual machine.
How this works
The site's server asks the chain's public node for the code at the address, the balance, and the number of transactions sent from it. When there is code, it asks Sourcify for the published source (or reads the on-chain bytecode when Sourcify has none) the same way as the token check. It only reads.
The UK Sanctions List comparison looks for the exact address in that saved copy. It does not ask the FCDO, and it does not use the chain you chose.
An address does not say who holds the key. This page cannot tell you who controls an account.
Information, not advice. A clean result does not make anything a good investment.