You & household
Applies an estimated employment-income deduction and social insurance. Treats the entered amount as business income after expenses.
Estimate income tax, resident tax, social insurance and take-home pay from income, household and deductions.
Free 2026 estimate of Japanese income tax, resident tax, social insurance and take-home pay based on salary, household details, deductions and side-business income.
Income
Enter the gross payment shown on your withholding slip. Enter side-business or miscellaneous income after expenses.
Deductions & credits
This is the individual iDeCo contribution, separate from an employer pension. It is deducted as a small-enterprise mutual-aid contribution. Uses occupancy year, acquisition type, energy class and qualifying household status to apply the enacted 2026 borrowing cap and credit period.
Ways to review your taxes
Three points for reviewing your tax and take-home pay
To understand your tax burden properly, check the income deductions and tax credits available to you, and classify all income—including side work—correctly. Compare this estimate with your withholding slip and deduction certificates.
Check which deductions you can claim
iDeCo, life insurance premium deductions, medical expense deductions, the home-loan tax credit and Furusato Nozei can reduce your tax when you meet the requirements. Check the eligibility rules and limits as well as the deductible amount.
Treat side work as income after expenses, not gross receipts
Tax on side work is generally based on income after necessary expenses have been deducted from receipts. Keep your books and receipts, and confirm the correct income category.
Separate year-end adjustment items from tax-return items
Some deductions, including medical expenses and the first year of the home-loan tax credit, cannot be handled through your employer’s year-end adjustment. Before filing, check the latest National Tax Agency guidance and the rules that apply to you.
Frequently asked questions about Japanese taxes and deductions
Will the estimate match my actual tax bill?
This is a simplified estimate. Actual tax and social insurance amounts vary by employer, municipality, insurance scheme, income type and the eligibility rules for each deduction.
Which year’s income is used to calculate resident tax?
As a rule, resident tax for the following fiscal year is calculated from the previous year’s income. To make annual costs easier to compare, this calculator displays an estimated annual resident-tax amount on the same screen.
If my side income is ¥200,000 or less, can I skip filing a tax return?
Employees whose salary has already been year-end adjusted may not need an income-tax return when non-salary income is ¥200,000 or less and certain other conditions are met. A resident-tax filing may still be required, and if you file an income-tax return for a medical expense deduction or another reason, the side income must also be reported. Check the rules for your circumstances.
Does the calculator reflect the 2026 tax reforms?
It reflects the 2026 revisions to the basic deduction and employment-income deduction. It does not cover every transitional measure or special case, so confirm the final amount using National Tax Agency guidance.
Which figure on my withholding slip should I enter?
For salary income, enter the “Amount paid” figure on your withholding slip. Do not enter the amount after the employment-income deduction or the total income deductions.
Does year-end adjustment complete every required procedure?
Deductions your employer can process may be handled through year-end adjustment. Medical expense deductions, the first year of the home-loan tax credit and certain side income may still require an income-tax return.
How are social insurance premiums calculated?
The calculator uses a simplified fixed rate for each work type. Actual premiums vary with standard monthly remuneration, the insurance scheme, location, age and other factors.
Can the home-loan tax credit also reduce resident tax?
Part of any amount that cannot be fully used against income tax may be deducted from the following year’s resident tax, subject to the applicable limit. This calculator models that mechanism in simplified form.
Can I also estimate my Furusato Nozei contribution limit?
The calculator uses your resident-tax estimate to show an approximate contribution that keeps your out-of-pocket cost at ¥2,000. The actual limit changes with household circumstances and other deductions, so check your municipality or service provider before contributing.
How much of the medical expense deduction is reflected?
The calculator subtracts an income-based threshold from the annual medical expenses you enter. It does not account for reimbursements such as insurance proceeds or the choice between this deduction and the self-medication tax system.
Is the blue-return special deduction applied automatically?
Not currently. For business income and certain other income, a special deduction of ¥100,000, ¥550,000 or ¥650,000 may be available depending on bookkeeping method, filing method, timely filing and other requirements.
Can home rent and communication costs be business expenses?
If the business-use portion can be clearly identified, that share may qualify as a necessary expense. Keep records of a reasonable allocation method—such as floor area, usage time or data usage—and the basis for your calculation.
How do the tax benefits of NISA and iDeCo differ?
Investment gains in an eligible NISA account are tax-free. Personal iDeCo contributions qualify for an income deduction and investment gains are also tax-free, but the funds generally cannot be withdrawn before age 60. Consider the purpose of the money and when you will need it.
Does incorporation always reduce tax for a sole proprietor?
Not necessarily. The result depends on income level, director compensation, social insurance, consumption tax, incorporation costs and ongoing expenses. Compare administrative work and fixed costs as well as the tax amount.