Summary
If you make 41,600,784 원 a year living in South Korea, you will be taxed 7,019,106 원. That means that your net pay will be 34,581,678 원 per year, or 2,881,807 원 per month. Your average tax rate is 16.9% and your marginal tax rate is 21.8%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of 100 원 in your salary will be taxed 21.82 원, hence, your net pay will only increase by 78.18 원.
Bonus Example
A 1,000 원 bonus will generate an extra 782 원 of net incomes. A 5,000 원 bonus will generate an extra 3,909 원 of net incomes.