Network setup

AchSwap runs on Arc Mainnet. Most wallets add it automatically when the app asks. If yours doesn't, add it with these values:

Wallet field	Value
Network name	Arc Mainnet
Chain ID	5042 (0x13b2)
RPC URL	https://rpc.mainnet.arc.io
Currency symbol	USDC
Block explorer	explorer.arc.io

Check the chain ID before you transact. A network with the right name but a different chain ID is not Arc Mainnet.

Arc has two block explorers: explorer.arc.io (Blockscout) and ArcScan. Both show transactions and balances. AchSwap's contract sources are verified on ArcScan, which is why these docs link there.

How USDC works on Arc

Arc uses USDC to pay network fees. That makes USDC special in two ways.

It is both a token and gas. The USDC you trade is the same balance your fees are paid from. Spend all of it and you can't pay for your next transaction. Keep a little back.

It shows up in two forms. The same balance can be read as:

Form	Address	Decimals	Used by
ERC-20	0x3600000000000000000000000000000000000000	6	Pools, approvals, most contracts
Native currency	none (sent as transaction value)	18	Gas, plain transfers

These are two views of one balance, not two tokens. For example, 2.5 USDC is 2500000 in the ERC-20 form and 2500000000000000000 in the native form. Sending from either one lowers the same balance.

What this means in practice:

• Don't add a "wrapped USDC" token for Arc. There isn't one to add.
• If your wallet shows USDC twice, both entries are the same money.
• AchSwap routes accept USDC in either form, which is why a USDC swap needs no approval.

Getting funds onto Arc

If your assets are on another chain, use the Bridge to move them to Arc. Bridging USDC to Arc gives you both something to trade and the gas to trade with.

Common tokens

Token	Address	Decimals
USDC	0x3600000000000000000000000000000000000000	6
EURC	0xbEf5f6d51CB62b58e6A8f77868681825C6fe21c1	6
cirBTC	0x171A4217b86A807A64eB94757Db6849fb4bDbAA0	8

The full list, with the protocol contracts, is in the contract reference.