Income Tax Calculator
Calculate income tax and tax refund/payment from salary, side income, medical expense deductions, and more.
Input
This is an approximation and may differ from actual amounts.
Result
How to Use
Enter your salary income, side income/miscellaneous income, medical expenses, additional social insurance deductions, and withheld tax amount. Income tax and the refund or additional payment for tax filing will be calculated automatically. Use this as a guide for tax returns when you have medical expense deductions or side income.
About the Formula
After applying the employment income deduction, basic deduction, social insurance deduction, and medical expense deduction are subtracted from total income to determine taxable income. Progressive tax rates (5%–45%) are applied, plus the reconstruction special income tax (2.1%) to calculate the income tax. The difference from withheld tax is the refund or additional payment. Housing loan credit and Furusato tax credit are not included.
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