Online Seller Margin Calculator Korea (Coupang, Smart Store, 11st: fees + VAT)

How it works

Platform fee = (sale price + shipping fee paid by the customer) × fee rate, plus 10% VAT on the fee. For a general VAT taxpayer, VAT payable per sale = output VAT in the sale (sale amount ÷ 11) − input VAT in your costs (product, shipping and ads ÷ 11) − VAT on the platform fee. Profit = sale amount − platform fee and its VAT − shipping − product cost − ads − VAT payable. Income tax is not included. Fee rates differ by category and platform and change over time, so they are inputs. Independent calculator, not affiliated with Coupang, NAVER or 11st.

⚠ Estimates for information only — not financial advice.

FAQ

Why divide by 11 for VAT?

A price that includes 10% VAT is 110% of the net price, so the VAT inside it is 10 ÷ 110 = 1/11 of the price.

What if I am a simplified (간이) taxpayer?

Simplified taxpayers pay VAT at a lower rate on sales and cannot deduct input VAT the same way; choose “Ignore VAT” for a rough check and ask a tax adviser for the exact figure.

Checked 11 Nov 2026. Value-Added Tax Act art. 30 (10% rate), art. 37–38 (output tax minus deductible input tax). Fee rates: enter them from each platform’s seller centre fee table for your category.