If you make $ 1,200,000 a year living in Taiwan, you will be taxed $ 136,053. That means that your net pay will be $ 1,063,947 per year, or $ 88,662 per month. Your average tax rate is 11.3% and your marginal tax rate is 13.6%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of $ 100 in your salary will be taxed $ 13.55, hence, your net pay will only increase by $ 86.45.
A $ 1,000 bonus will generate an extra $ 865 of net incomes. A $ 5,000 bonus will generate an extra $ 4,323 of net incomes.