If you make 300,000,- kr a year living in the region of Horsens, Denmark, you will be taxed 102,616, kr. That means that your net pay will be 197,384,- kr per year, or 16,449,- kr per month. Your average tax rate is 34.2% and your marginal tax rate is 40.3%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of 100,- kr in your salary will be taxed 40.34,- kr, hence, your net pay will only increase by 59.66,- kr.
A 1,000,- kr bonus will generate an extra 597,- kr of net incomes. A 5,000,- kr bonus will generate an extra 2,983,- kr of net incomes.