If you make 300,000,- kr a year living in the region of Sorø, Denmark, you will be taxed 105,234, kr. That means that your net pay will be 194,766,- kr per year, or 16,230,- kr per month. Your average tax rate is 35.1% and your marginal tax rate is 41.4%. 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 41.43,- kr, hence, your net pay will only increase by 58.57,- kr.
A 1,000,- kr bonus will generate an extra 586,- kr of net incomes. A 5,000,- kr bonus will generate an extra 2,929,- kr of net incomes.