Bridge DAI to Polygon

WHAT IT DOES

This tool enables you to bridge DAI (MakerDAO's stablecoin) from Ethereum Mainnet to Polygon (formerly Matic Network) using the official Polygon Proof-of-Stake (PoS) bridge. It reads your current DAI balance on Ethereum Mainnet, checks your allowance for the Polygon bridge contract, and handles the approval process automatically if needed. The tool then submits a deposit transaction to the Polygon bridge, transferring your specified amount of DAI to the Polygon network.

The tool uses the official Polygon PoS bridge (L1ERC20Bridge) and is specifically designed for Ethereum Mainnet (chain ID 1). It handles the complex ERC-20 approval and bridge deposit mechanics automatically, making it easy to move DAI from Ethereum to Polygon without needing to understand the underlying bridge protocol. Polygon offers significantly lower transaction fees than Ethereum Mainnet while maintaining high security through its checkpoint mechanism.

HOW TO USE

Connect your wallet using the "connect" button. Ensure you are connected to Ethereum Mainnet (chain ID 1) — the tool will display your current chain ID and DAI balance. Enter the amount of DAI you wish to bridge to Polygon in the input field. The tool will display the bridge contract address, your current allowance for the bridge, and estimate the gas cost for the deposit transaction.

Review the bridge summary, then click "bridge DAI → Polygon" to start the process. If your allowance is insufficient, the tool will automatically request approval for the bridge to spend your DAI. After approval is confirmed, it will submit the deposit transaction. The tool will wait for confirmation and display the transaction details on Etherscan. After the transaction is confirmed on Ethereum Mainnet, your funds will be processed by the Polygon bridge and will appear on Polygon. This process typically takes 15-30 minutes, depending on network congestion and Polygon's checkpoint intervals.

TECHNICAL MECHANISM — POLYGON POS BRIDGE DEPOSIT WITH ERC-20 APPROVAL

The tool interacts with the Polygon L1ERC20Bridge contract, which serves as the entry point for depositing ERC-20 tokens from Ethereum to Polygon. The bridge's depositERC20For() function accepts the L1 token address (DAI on Ethereum), the recipient address, and the amount to deposit. Before calling the bridge, the tool checks the user's DAI allowance for the bridge contract using the allowance() function.

If the allowance is less than the amount to bridge, the tool submits an approve() transaction to the DAI contract, granting the bridge permission to spend the specified amount. Once approval is confirmed, the tool proceeds with the bridge deposit. The bridge contract locks the DAI on L1 and sends a message to the Polygon L2 inbox, which the Polygon validators process to mint the equivalent amount of DAI on L2. The bridge uses a checkpoint mechanism where validators periodically submit snapshots of the Polygon chain state to Ethereum, ensuring the security of the deposit. This checkpoint interval is why deposits take 15-30 minutes to complete, as the deposit must be included in a checkpoint before it is finalized.

WHAT IT CANNOT SEE

This tool cannot estimate exact gas costs without a live RPC call, and gas prices on Ethereum Mainnet may change between quoting and execution. It cannot guarantee bridge finality times — while typical deposits take 15-30 minutes, network congestion or Polygon validator delays may extend this time. The tool cannot verify the bridge contract address is correct beyond the pre-configured mapping, and if the mapping becomes outdated, the transaction could fail or be sent to the wrong contract. It cannot cancel a transaction once submitted, and if the transaction fails due to gas issues, approval errors, or contract issues, you may still pay gas fees. The tool cannot handle bridging from non-Ethereum chains, nor can it bridge tokens other than DAI. It also does not support bridging from Polygon back to Ethereum.

PLEASE NOTE — ETHEREUM MAINNET ONLY

This tool works exclusively on Ethereum Mainnet (chain ID 1). You must be connected to Ethereum Mainnet to use this tool. It does not support bridging from other networks such as Polygon itself, BNB Smart Chain, or other EVM chains. The tool only bridges DAI (ERC-20) — it does not support native ETH or other ERC-20 tokens. Always verify that you are connected to the correct network and that the bridge contract address displayed matches the official Polygon bridge address before submitting a transaction. Using the wrong network or an outdated contract address will result in transaction failure and loss of gas fees. DAI on Polygon is a bridged version of the stablecoin, and while it is widely supported, always confirm the token address on Polygon for your specific use case.