What is Token approval?

Permission you grant a smart contract to move a specific token from your wallet — the mechanism behind most connect-wallet flows, and a top attack vector.

How it works

Approvals are how DEXs and protocols spend your tokens. The danger is unlimited or stale approvals: a malicious or compromised contract can drain an approved token. Regularly auditing and revoking approvals you no longer use is core hygiene.

Example

In practiceYou approve a DEX router to spend your USDC; later you revoke that approval so the router can no longer move it.

How often should I revoke approvals?

Any time you're done with a protocol, and periodically for old ones. Unlimited approvals to contracts you don't recognize are the ones that hurt.

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