"Dust" refers to a small amount of cryptocurrency under the minimum tradable limit that remains in your wallet after executing a transaction. Coinbase generally considers dust to be any amount of crypto valued at less than $0.02 in your local currency.
To remove dust from your account, you have two options:
Send it to another Coinbase customer's email address or phone number.
Select Sell and choose the asset you want to remove. You can sell it for no proceeds, it’ll be removed from your account, and you’ll receive an email and notification confirming that the removal was successful.
Note: This option will only be presented for amounts less than $0.02 in local currency value and is not currently available for Advanced Trade.