If you make Rp. 600,000,000 a year living in Indonesia, you will be taxed Rp. 136,684,000. That means that your net pay will be Rp. 463,316,000 per year, or Rp. 38,609,667 per month. Your average tax rate is 22.8% and your marginal tax rate is 32.1%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of Rp. 100 in your salary will be taxed Rp. 32.10, hence, your net pay will only increase by Rp. 67.90.
A Rp. 1,000 bonus will generate an extra Rp. 679 of net incomes. A Rp. 5,000 bonus will generate an extra Rp. 3,395 of net incomes.