Summary
If you make 7,909,200 円 a year living in Japan, you will be taxed 2,075,902 円. That means that your net pay will be 5,833,298 円 per year, or 486,108 円 per month. Your average tax rate is 26.3% and your marginal tax rate is 25.7%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of 100 円 in your salary will be taxed 25.74 円, hence, your net pay will only increase by 74.26 円.
Bonus Example
A 1,000 円 bonus will generate an extra 743 円 of net incomes. A 5,000 円 bonus will generate an extra 3,713 円 of net incomes.