Summary
If you make 51,090,000 kr a year living in the region of Frederiksberg, Denmark, you will be taxed 23,592,332 kr. That means that your net pay will be 27,497,668 kr per year, or 2,291,472 kr per month. Your average tax rate is 46.2% and your marginal tax rate is 46.4%. 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 46.36 kr, hence, your net pay will only increase by 53.64 kr.
Bonus Example
A 1,000 kr bonus will generate an extra 536 kr of net incomes. A 5,000 kr bonus will generate an extra 2,682 kr of net incomes.