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What is a crypto bridge?
A bridge is a service that moves tokens or information from one blockchain to another. Usually it locks your tokens on the first chain and issues a matching wrapped token on the second, which can be redeemed back through the bridge.
What it means for you
The wrapped token you receive is only worth what the bridge can redeem, so a bridge hack or bug can leave it unbacked; very large sums have been stolen this way. Some bridges are run by a small group of operators who could block or take funds. Check that the destination chain and token address are correct before sending.
A common mistake: “The bridged token is the same coin as on the original chain.”
In fact: Through lock and mint it is a representation issued by the bridge. If the locked reserve is stolen or the bridge fails, it can lose its backing while still sitting in your wallet.
How it works
Bridges move value in three ways: lock and mint (tokens locked in a contract on the source chain, a representation minted on the destination), burn and mint (tokens destroyed on one chain and issued on the other), and atomic swaps with another party. Something must confirm what happened on the source chain. Some bridges rely on an outside set of verifiers, such as a multisig federation, an MPC group or an oracle network, which is fast but adds parties who can fail or collude; others rely on the connected chains' own validators.
Sources: ethereum.org: Blockchain bridges, ECB Macroprudential Bulletin: Decentralised finance, ethereum.org: Bridges (developer docs) · checked 4 October 2026
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Educational content, not financial advice. Written by hand and checked against the source named above. Something wrong? Tell us and we reply within two business days.