Position Size Calculator
Decide how many shares to buy so that, if your stop-loss is hit, you lose no more than the share of capital you choose to risk.
Enter capital, entry and stop-loss above 0, with the stop-loss different from the entry.
A stop-loss below the entry is a long (buy) trade; above the entry is a short (sell) trade.
- Amount at risk —
- Risk per share —
- Loss if stop-loss is hit —
- Share of capital used —
- Position value —
Limited by your capital: the risk you chose allows more shares than your capital can buy without leverage.
Frequently asked questions
How is position size calculated?
The amount you are willing to lose (capital × risk %) is divided by the loss per share if your stop-loss is hit (the gap between entry and stop-loss). The result, rounded down, is the number of shares to buy.
What risk per trade should I use?
Many traders risk 1% to 2% of their capital on a single trade, so a run of losing trades does not wipe out the account. The right figure depends on your own risk appetite.
Why is the number of shares sometimes limited by capital?
When the stop-loss is very close to the entry, the risk you chose can allow more shares than your capital can pay for. The calculator then caps the position at what your capital can buy without leverage.
Is my loss guaranteed to stay within the risk amount?
No. A stop-loss order can be filled at a worse price if the market gaps or moves quickly, and brokerage and charges are not included, so the actual loss can be larger.
Disclaimer: This calculator is for illustration and education only and is not a recommendation to buy or sell any security. Results exclude brokerage, taxes and statutory charges.
Investments in securities market are subject to market risks; read all the related documents carefully before investing.