Summary
If you make 302,400,030 원 a year living in South Korea, you will be taxed 107,499,022 원. That means that your net pay will be 194,901,008 원 per year, or 16,241,751 원 per month. Your average tax rate is 35.6% and your marginal tax rate is 44.7%. 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 44.65 원, hence, your net pay will only increase by 55.35 원.
Bonus Example
A 1,000 원 bonus will generate an extra 554 원 of net incomes. A 5,000 원 bonus will generate an extra 2,768 원 of net incomes.