If you make 1,000,000 kr a year living in Norway, you will be taxed 333,143 kr. That means that your net pay will be 666,857 kr per year, or 55,571 kr per month. Your average tax rate is 33.3% and your marginal tax rate is 43.8%. 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 43.79 kr, hence, your net pay will only increase by 56.21 kr.
A 1,000 kr bonus will generate an extra 562 kr of net incomes. A 5,000 kr bonus will generate an extra 2,811 kr of net incomes.