The two calculations
In Costs, Actual costs or mileage rate shows the Mileage rate applied to your business miles, and the Actual costs × business share: fuel, service, insurance and other costs, times the share of business miles in the distance on the odometer. A sentence says which one gives more.
The rates
A dated preset for your country (IRS, HMRC, CRA, ATO, and more) or Your rates. The business miles come from the trips you record with a purpose. The app compares two calculations; it does not tell you what to claim, and each country's rules decide.