Summary
If you make 488,748,000 원 a year living in South Korea, you will be taxed 192,035,431 원. That means that your net pay will be 296,712,569 원 per year, or 24,726,047 원 per month. Your average tax rate is 39.3% and your marginal tax rate is 46.2%. 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 46.16 원, hence, your net pay will only increase by 53.84 원.
Bonus Example
A 1,000 원 bonus will generate an extra 538 원 of net incomes. A 5,000 원 bonus will generate an extra 2,692 원 of net incomes.