If you make 300,000 kr a year living in the region of Herlev, Denmark, you will be taxed 92,860 kr. That means that your net pay will be 207,140 kr per year, or 17,262 kr per month. Your average tax rate is 31.0% and your marginal tax rate is 31.0%. 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 31.01 kr, hence, your net pay will only increase by 68.99 kr.
A 1,000 kr bonus will generate an extra 690 kr of net incomes. A 5,000 kr bonus will generate an extra 3,450 kr of net incomes.