VAT Calculator
Adds or removes the 10% VAT and splits a total into supply value and tax for invoice lines.
VAT under the 부가가치세법 (Value-Added Tax Act) is a flat 10%, which makes the forward calculation trivial and the reverse one a common mistake: removing VAT from a tax-inclusive total is dividing by 1.1, not subtracting 10%. This does both and splits a total into 공급가액 and 세액 the way an invoice line needs.
Calculated on the 2026 rates.
2026년 기준 · 소득세법 §55 (Income Tax Act, art. 55) basic rates, 6–45% · 지방소득세 10% of the tax
The employer-side contributions (고용안정·직업능력개발, 산재보험) vary with headcount and industry, so an average is used here. Your actual invoice will differ.
Rates change every year. If this still reads 2026 after 2026 has passed, the figures are out of date.
One amount
Works back from the total to the supply value and the tax. This is the card-receipt case.
Commas and “원” are ignored.
Result
공급가액 — supply value
1,000,000원
부가세액 — VAT
100,000원
합계금액 — total
1,100,000원
10%, truncated to the won. Working back from a total, the supply value is truncated first and the tax is the remainder, so supply + tax matches the total exactly — computing each separately puts them 1 won apart about half the time, and an e-tax invoice is rejected over that 1 won.
By invoice line
The tax is truncated for each line and then summed. Adding the supply values first and taxing the sum comes to a few won different, and the figure that has to match the 세금계산서 is the per-line one.
How to use it
Enter the amount and say which it is
공급가액 (before tax) or 합계금액 (including tax). Getting this backwards is the error the tool exists to prevent.
Take the three figures for the invoice
공급가액, 세액 and 합계금액 are the three columns a 세금계산서 line needs, and they must add up exactly.
Watch the rounding on a reverse calculation
A tax-inclusive total rarely divides into whole won. Which way the fraction is taken is a matter of agreement between the parties, so check that both sides used the same rule before the totals are compared.
Common questions
Is everything taxed at 10%?
No. Exports are zero-rated and a list of supplies — certain foodstuffs, medical and educational services, residential rent among them — is exempt under the 부가가치세법. This calculator applies the standard rate; whether a supply is standard-rated, zero-rated or exempt is a question about the transaction.
What is the difference between exempt and zero-rated?
Both charge no output VAT, but zero-rating keeps the right to deduct input VAT and exemption removes it. For a business, that difference is the whole point — an exempt trader bears the VAT on its own purchases.
Does this file a return?
No. It computes line amounts. The 부가가치세 신고 is output tax against input tax over a period, filed at 홈택스, and is a different exercise entirely.
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