Comprehensive Income Tax Calculator
Enter yearly revenue and an expense rate or amount to get business income, tax base, income tax, local income tax and your effective rate.
How to use
- Enter your yearly revenue — the gross income of your business.
- Choose how expenses are handled: apply an expense rate, or type the actual expense amount.
- With the expense rate, enter the simplified or standard rate for your industry. If you keep books, switch to entering expenses directly.
- Set the number of dependents and any extra tax credits such as a retirement pension or pension account credit.
- Total tax, business income, tax base, calculated tax, local income tax, after-tax income and the effective rate appear at once.
FAQ
Where do I find the expense rate?
The Korean National Tax Service publishes simplified and standard expense rates by industry every year. Look up your industry code on Hometax or the NTS website.
What is the difference between the simplified and standard rate?
The simplified rate recognises expenses as a fixed share of revenue. The standard rate recognises key costs (purchases, wages, rent) at their real amounts and applies the rate to the rest. Which one applies depends on your filing requirements.
How is the personal deduction applied?
1.5 million won is deducted from business income for every dependent, including you.
Will this match my filed return?
No. It is a quick estimate — the real figure moves with your industry rate, whether you file in good faith and the deductions or reductions you claim. File through Hometax or with a tax professional.
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