On-Chain

On-chain describes anything recorded directly on a blockchain's public ledger, where it is validated by the network, stored permanently and visible to anyone. An on-chain transfer, swap or smart contract call settles by consensus rather than in a company's internal database, which is what makes it independently verifiable and hard to censor — but also why it costs a gas fee and cannot simply be reversed if you send to the wrong address. The opposite is off-chain, where activity happens outside the ledger, for example trades matched inside an exchange's own books. Because on-chain records are public and permanent, addresses can be linked and analysed years later, so treat on-chain activity as a permanent public record rather than a private one.