Token allowances

To use tokens and NFTs in decentralised applications such as Uniswap or OpenSea you have to grant the application permission to spend tokens on your behalf - known as an allowance. Allowances are an important part of using these apps, but can be dangerous if left unchecked.

Risks of allowances

Bugs can exists and exploits can happen even in established projects, and by approving token allowances you are potentially exposing your wallet to these exploits. To keep yourself safe from allowance exploits it is a good practice to regularly inspect and revoke your allowances. Besides revoking you should also be mindful of the allowances that you approve in the first place.

Revoke.cash

Revoke.cash comes in as a preventative tool to manage your token allowances and practice proper wallet hygiene. By regularly revoking active allowances you reduce the chances of becoming the victim of allowance exploits.

Read more

To read about Ethereum token allowances in more depth, make sure to read the article Unlimited ERC20 allowances considered harmful. Also check out the FAQ for a quick overview of the most frequently asked questions about allowances and Revoke.cash.

Credits

Revoke.cash was created by Rosco Kalis in 2019, and since then it has grown to be a staple in web3 security. For the Ethereum chain and several other chains allowance data is retrieved directly from the blockchain. For most other chains a combination of Etherscan, Blockscout and Covalent APIs are used.