📊 Position Size Calculator
Enter your account balance, the percentage you're willing to risk, and your entry and stop-loss prices to see the dollar risk, the per-share risk, and how many whole shares a fixed-fractional model would size — plus the resulting position value.
🧮 Size a Position by Risk
What is a Position Size Calculator?
It answers a purely arithmetic question: given how much you're prepared to risk on one idea and how far your stop-loss sits from your entry, how many shares does that imply? Enter the balance, the risk percentage, the entry, and the stop, and it computes the dollar risk, the per-share risk, and a whole-share count, then shows what that position is worth and what fraction of the account it uses.
Traders study position sizing as a way to make each loss consistent and survivable, but the figures here are illustrative, not a suggestion to take any particular trade. Markets gap, orders slip, and fees apply, so treat the output as a starting estimate and verify everything against your broker.
❓ Frequently Asked Questions
How is position size calculated?
A common fixed-fractional method multiplies your account balance by the percentage you're willing to risk to get a dollar risk amount, works out the per-share risk as the distance between your entry and stop-loss price, then divides the dollar risk by the per-share risk and rounds down to a whole number of shares. This is a way to compute a size, not a recommendation to take any trade.
What does 'risk per trade' mean?
It's the fraction of your account you would lose if the stop-loss is hit, expressed as a percentage. Many educational sources discuss keeping this small so a single loss is survivable, but the right figure is personal and depends on your circumstances. This tool simply applies whatever percentage you enter.
Does the calculator account for fees, slippage, or gaps?
No. It performs pure arithmetic on the four numbers you enter and assumes your order fills exactly at the entry and stop prices. Real trades can gap past a stop or fill at a worse price, so an actual loss may exceed the modelled risk amount.
Is this financial advice?
No. This calculator is for educational and informational purposes only and does not recommend buying or selling anything. Trading involves substantial risk of loss; consult a licensed financial advisor before making decisions.