Amazon gives you the ACoS measurement on the performance of your ads. The lower the ACoS, the better performs your ad campaign and the more money you make.
The ACoS is calculated by using the cost of spending and dividing it by sales. This number doesn’t tell you anything until you have figured out your break-even point.
The break-even point can be defined as a point where total costs (expenses) and total sales (revenue) are equal.
In order to profit from the ad campaign, the ACoS needs to be lower than your break-even point! For this reason, we have developed the royalty and break-even calculator for Kindle, paperback, and for the combined overall based on book ratio.
You will find these new calculators under the tools section in your menu.