What is the Stock Return Calculator?
The Stock Return Calculator is a tool that accurately calculates your actual net profit and return rate by factoring in trading commissions and securities transaction tax. Instead of just looking at the difference between buy and sell prices, you can see the real amount you take home.
It provides default values for Korea's 2026 securities transaction tax (0.18%) and online trading commission (0.015%), which you can freely adjust. It also automatically calculates the break-even selling price so you know the minimum price to sell at to avoid losses.
Key Features
Real-time P&L Calculation
Enter buy price, sell price, and quantity to instantly calculate net profit and return rate including all fees and taxes.
Commission & Tax Included
Reflects both buy/sell commissions and securities transaction tax for accurate real-world profit calculation.
Auto Break-even Calculation
Automatically calculates the minimum sell price (break-even point) considering all commissions and taxes.
Comma-formatted Numbers
Large amounts are automatically formatted with thousand separators for easy reading, and results can be copied.
How to Use
- Enter Buy Info — Input the buy price per share and the number of shares.
- Enter Sell Price — Input the actual or expected sell price per share.
- Check Fees & Tax — Review defaults (commission 0.015%, tax 0.18%) and adjust if needed.
- View Results — Check net profit, return rate, and break-even sell price.
Use Cases
Pre-sell Profit Simulation
Calculate how much actual profit you would make if you sold your shares at a specific price.
Target Return Reverse Calculation
Find out the minimum sell price needed to achieve your desired profit target.
Broker Fee Comparison
Compare actual profits across different brokers by entering their respective commission rates.
Break-even Point Check
Identify the minimum sell price after fees and taxes to prevent losses.
Frequently Asked Questions
What is securities transaction tax?
Securities transaction tax is a tax imposed when selling stocks. As of 2026 in Korea, both KOSPI and KOSDAQ have a 0.18% tax rate. No tax is charged on purchases — only on the sell amount.
How is commission calculated?
Commission is charged on both buy and sell transactions. It is calculated by multiplying the trade amount (price x quantity) by the commission rate. Rates vary from 0.003% to 0.5% depending on the broker and trading method (online/offline/mobile). The default 0.015% represents the online trading average.
What is the break-even point (BEP)?
The break-even point is the price at which you neither profit nor lose, after accounting for all fees and taxes. You must sell above this price to generate actual profit. It factors in buy commission, sell commission, and securities transaction tax.
What is the 2026 transaction tax rate?
As of 2026, both KOSPI and KOSDAQ have a securities transaction tax rate of 0.18%. This has been gradually reduced from 0.20% in 2023. Note that the special rural development tax is separate. This calculator only reflects the securities transaction tax.
Is my data stored?
No. This calculator processes all calculations in your browser. Your trading information is never sent to any server. All data is cleared when you close the page.
Privacy Notice
This stock return calculator processes all calculations in your browser. Your buy/sell information is never sent to any server, and no investment data is stored.