Position size calculator
Risk-based position sizing is the core of money management. Enter how much of your account you're willing to risk and your stop-loss distance, and this calculator returns the lot size that keeps your loss within that limit.
Contract size · Pip size
These are typical standard values — they vary by broker and instrument, so confirm and adjust them to match your own account.
Result
- Amount at risk
- 100.00 USD
- Pip value (1 lot)
- 10.00 USD
- Recommended lots
- 0.50
- Position units
- 50,000
- Money per pip
- 5.00 USD
How to use it
- 1 Enter your account balance and the percentage you want to risk on the trade.
- 2 Enter your stop-loss distance in pips.
- 3 Pick your instrument (adjust the contract size and pip size to match your broker if needed).
- 4 Read the recommended lot size and the money at risk per pip.
How the position size is calculated
Risk amount = balance × risk %. Lot size = risk amount ÷ (stop-loss in pips × pip value per lot). Keeping risk to a small, fixed percentage of your account on each trade is a common risk-management rule.
Frequently asked questions
How much should I risk per trade?
Many traders limit risk to 1–2% of account equity per trade, but this is a personal risk decision, not advice. The calculator works with whatever percentage you enter.
What is a lot?
A lot is a standardized trade size. In forex, one standard lot is 100,000 units of the base currency; a mini lot is 0.1 and a micro lot is 0.01. The calculator returns the lot size as a decimal you can round to your broker's minimum step.
Does this include spread and commission?
No. The result sizes your position by stop-loss risk only. Real costs such as spread, commission, swap and slippage will affect your actual loss — always confirm them with your broker.
Put the numbers to work
Practice these positions risk-free on the Merini demo — real-time charts and paper trading with virtual funds, in your browser, no install.
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※ 本内容仅供信息与教育之用,并非投资建议或劝诱。交易条件(交易时间·保证金·手续费·点值等)因交易所·券商·时点·夏令时而异,实际交易前请在您使用的券商处自行确认。衍生品交易可能造成超过本金的损失。