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/ ERC20 Permit Generator

Security Warning: Never share your private key. This tool demonstrates the EIP-2612 permit structure. For production use, integrate with a wallet (MetaMask, WalletConnect) to sign permits client-side.

Owner Address

Spender Address

Token Amount (in wei/raw units)

Token Contract Address

Chain ID

1 = Ethereum, 137 = Polygon, 42161 = Arbitrum, 10 = Optimism

Deadline (optional - defaults to 24h from now)

Nonce

Usually 0 for the first permit. Query the contract for the current nonce.

Private Key (Optional - Not Recommended)

/ Selected Tool

ERC20 Permit Generator

Generate EIP-2612 permit signatures for gasless approvals

■ 01

What is EIP-2612 Permit?

EIP-2612 introduces a permit function for ERC-20 tokens that allows users to approve token transfers with a signature instead of a transaction. This enables gasless approvals where the spender can execute both the appro…

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How does it work?

How Permits Work Instead of calling approve() which costs gas, users sign an off-chain message (EIP-712) containing the approval details. The spender then submits this signature along with the permit details to the toke…

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Sample Cases

Covers USDC Permit on Ethereum, DAI Permit - Polygon Network, and Custom Token Permit - Arbitrum so you can compare common inputs and outputs quickly.

/ Code

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/ Integration

Source code from the selected tool, shown here alongside the live version on the right.

/ Source Code

TypeScript

typescript

// npm install viem

import { signTypedData } from 'viem/accounts';
import { privateKeyToAccount } from 'viem/accounts';

interface PermitData {
  owner: string;
  spender: string;
  value: string;
  nonce: string;