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    Lot Size Calculator

    Determine the optimal lot size for your trade based on your risk percentage and stop-loss level. An essential tool for capital management.

    Quick answer

    A lot size calculator sets the right position size from your account balance, the percentage you are willing to risk and your stop-loss distance in pips. Enter those three inputs and it returns the number of lots that keeps your worst-case loss equal to the risk you chose.

    Calculator

    Enter the details to calculate the appropriate lot size

    The 2% Rule

    The 2% Rule is a common risk management strategy stating you should not risk more than 2% of your capital on a single trade.

    Practical Example:

    • Balance: $10,000
    • Risk 2%: $200
    • 50-pip stop loss
    • Lot size: 0.4

    Benefits of This Rule:

    • Protects your capital
    • Stay in the market longer
    • Reduces psychological pressure
    • Sustainable account growth

    Learn More About Risk Management

    Join our risk management course to learn how to use these calculations professionally

    How to size a position and why everything starts with risk

    The formula that protects your capital

    Lot size is not a preference; it is the output of three inputs: capital, risk per trade and stop distance in pips. Lot size = (capital × risk %) ÷ (stop pips × pip value). You decide the money you accept losing, then pick the size that makes it your maximum loss.

    Example: 5,000 dollars, 1% risk (50 dollars), a 25-pip stop. With a ten-dollar pip on a standard lot the right size is 0.2 lots. Size grows as the stop tightens and shrinks as it widens, so a volatile market needing a wider stop demands a smaller size — that is risk management in one line.

    Using the calculator in practice

    Start with a conservative 0.5%–1% risk per trade. At that level ten losses in a row still leave over 90% of your capital, which gives you the mental room to keep one plan instead of rewriting it after every loss.

    • Enter your real balance, not the amount you plan to deposit later.
    • Fix your risk percentage once and apply it to every trade.
    • Place the stop at a logical technical level, then enter its distance in pips.
    • Take the resulting lot size as it is; never round it up to chase profit.
    • Recalculate as your balance changes so size grows with the account.

    From correct sizing to consistent results

    Most blown accounts fail not because the analysis was wrong but because size was too large for the stop. With correct sizing a loss becomes an ordinary cost within a series of trades, and the urge to move stops or double up disappears.

    Pair this with the pip calculator for profit and loss and the margin calculator to confirm leverage is not locking too much of your balance, then revisit the academy risk-management lessons on reward-to-risk and judging a plan over a hundred trades rather than one. Educational only, not investment advice.

    Frequently asked questions about this tool