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Bridge Tokens with Etherscan

How to bridge ERC-20 tokens from Ethereum and Polygon to Celo.


Approve the Bridge

Start by approving token usage on the bridge.

  • Navigate to the Etherscan (or Polygonscan) page for the token you want to send
  • Open the Write Contract pane > connect your wallet > and select approve

Bridging Tokens with Etherescan 1

  • For spender enter the BridgeRouter address:
Ethereum BridgeRouter Address = 0x4fc16De11deAc71E8b2Db539d82d93BE4b486892
  • For amount enter the number of tokens you'd like to send in that token's smallest unit.
tip

If you're unsure, check the decimals in the Read Contract pane

  • For most tokens the number of digits is 18
  • The + button next will help you fill in the right number
info

Approving too much is usually ok, but not approving enough will cause your next transaction to fail.

  • Select write > sign the transaction > then send it to the network.

Call the Bridge

You can now start sending tokens on the approved Bridge.

  1. Navigate to the appropriate page for the router
Address = [0x4fc16De11deAc71E8b2Db539d82d93BE4b486892](https://etherscan.io/address/0x4fc16De11deAc71E8b2Db539d82d93BE4b486892)
  • Open the Write as Proxy pane > connect your wallet > and select send

Bridging Tokens with Etherescan 2

  • For _token, enter the address of the token you want to send
  • For _amount, enter the amount of tokens you'd like to send in that token's smallest unit.
info

This should be the same number you approved earlier.

  • For _destination, enter the domain ID of the chain to which you'd like to send tokens.
Celo Domain ID = 1667591279
tip

Domain IDs are like phone numbers. They represent the chain you're going to call.

  • For _recipient, enter the address of the recipient on the destination chain.
    • To help support future chains with longer addresses, Optics uses 32-byte addresses.
    • To convert an Ethereum, Celo, or Polygon address to bytes32 you can add 24 0s after the 0x prefix
tip

Before: bytes32

0x6a39909e805A3eaDd2b61fFf61147796ca6aBB47

After: 24 Zeros after 0x Prefix

0x0000000000000000000000006a39909e805A3eaDd2b61fFf61147796ca6aBB47
  • Select write > sign the transaction > then send it to the network.

Wait

Wait for a moment for your transaction to finalize on the network.