What does gross/net mean?

An amount without taxes is the net amount, an amount that already contains taxes is the gross amount. So if you add the percentage of taxes, in Germany either 7% or 19% - depending on the goods or services - to the net amount, you get the gross amount. The other way around, if you subtract the tax rate from the gross amount, you get the net amount. The tax amount is the difference between the gross and the net amount or the percentage value you get when you calculate e.g. 19% of the net amount.
All these values can be calculated with our online VAT calculator, you only need 2 of the values, the other two values are then calculated.