Swap Tokens - Base Documentation

What You Can Ask

Swap 100 USDC for ETH on Base

Buy $50 of ETH with USDC

Trade 0.01 ETH for USDC

Convert all my USDC to ETH

How It Works

The swap tool prepares a token swap and requires your approval in Base Account. Swaps are only supported on mainnet chains — not on testnets.

Parameter	Required	What it does
`fromAsset`	Yes	Token to swap from — symbol (`USDC`) or contract address
`toAsset`	Yes	Token to swap to — symbol (`ETH`) or contract address
`amount`	Yes	Amount of `fromAsset` to swap (human-readable decimal)
`chain`	Yes	Target mainnet chain, e.g. `base`, `ethereum`, `arbitrum`, `optimism`, `polygon`, `bsc`, or `avalanche`

Testnet swaps are not supported. If you need to test, use send on base-sepolia instead.

Approval Flow

Same as sending — every swap requires approval in Base Account. Your assistant will give you a link to review the swap details before anything is signed.

Send Tokens

Send tokens directly to another address.

Check Balance

Verify balances before swapping.