Summary
If you make 46,800,000 원 a year living in South Korea, you will be taxed 8,188,317 원. That means that your net pay will be 38,611,683 원 per year, or 3,217,640 원 per month. Your average tax rate is 17.5% and your marginal tax rate is 22.7%. 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 22.66 원, hence, your net pay will only increase by 77.34 원.
Bonus Example
A 1,000 원 bonus will generate an extra 773 원 of net incomes. A 5,000 원 bonus will generate an extra 3,867 원 of net incomes.