VAT Calculator
Turn a VAT-exclusive supply value or a VAT-inclusive total into the VAT, the supply value and the total, laid out in the lines a tax invoice needs.
How to use
- Type an amount, then pick whether it is the supply value (VAT excluded) or the total (VAT included).
- Check the rate: 10% for a standard taxable business, 0% for exempt and zero-rated supplies.
- The VAT, supply value and total appear instantly, and the copy button hands you the three lines to paste.
- Use the table to fill in each line of a tax invoice.
FAQ
What is the difference between the two bases?
On the supply-value basis the amount you typed has no VAT in it and the VAT is added. On the total basis the amount already includes VAT, so the supply value is that amount divided by 1 + rate.
Does it match what goes on an invoice?
It uses the same arithmetic and rounds the VAT to the won. A billing system that truncates instead of rounding can differ by a few won.
Can an exempt business use it?
Yes. Set the rate to 0 and the VAT is 0, so the supply value and the total are the same number.
Does it work for simplified taxation?
Yes — enter whatever rate applies to you. Ask the tax office for the sector values used to work that rate out.
Related tools
Freelancer 3.3% Withholding Calculator
Work out the take-home pay on a Korean freelance contract after the 3.3% withholding — 3% income tax plus 0.3% local income tax — including when the small-amount rule drops the tax to zero.
Year-End Tax Refund Calculator
Enter your yearly gross salary and the tax already withheld to see whether you get a refund or owe more, recalculated with the 2026 basic tax rates.
Employer Payroll Cost Calculator
Enter a monthly wage and see what an employer actually pays: the employer share of the four insurances, the severance accrual and the annual payroll cost.
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.