EIP-2612 (Permit)
An Ethereum token standard letting a user approve a spender through an off-chain signature instead of a separate on-chain transaction, saving a step and its gas cost.
EIP-2612, commonly called "permit," is a token standard that lets a user grant a token approval (see Kaavon's "Token Approval" glossary definition) to a spender by signing an off-chain message using the EIP-712 (see Kaavon's "EIP-712 (Typed Structured Data Signing)" glossary definition) format, rather than submitting a separate, gas-costing on-chain approval transaction beforehand. The spender can then submit the user's signature along with their main transaction, which verifies the signature and processes the approval and the intended action together in a single transaction.
This removes a common two-transaction friction point in DeFi — approve, then act — collapsing it into one transaction and saving the gas cost of the separate approval step entirely, since the signature itself is free to produce off-chain. Not every token implements EIP-2612, since it requires the token's contract to specifically support it, which is why wrapper standards like Permit2 emerged to extend similar signature-based approval convenience to tokens that don't natively implement EIP-2612 themselves.
Examples
- A DeFi app supporting EIP-2612 can let a user approve and swap a token in a single transaction, rather than requiring a separate approval transaction beforehand.
- Because EIP-2612 support must be built into a token's own contract, not every token benefits from this gas-saving approval pattern.