Position Size Calculator
Turn your risk percentage and stop-loss into an exact lot size — works for forex, metals, energy and index CFDs, with fully editable contract specs.
What it is
A position size calculator answers the most important number in every trade: how many lots to open. The logic is "risk first, size second" — you decide the maximum percentage of your account you are willing to lose on one trade (a common convention is 1%–2%), then combine it with your stop-loss distance to work backwards to a lot size that keeps the loss within that limit. Oversized positions are one of the fastest routes to a deep drawdown; fixing your per-trade risk at a small percentage leaves enough room to survive a losing streak and wait for the next setup.
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Calculate your position size
Enter your account and stop-loss — get the lot size instantly. All math runs in your browser.
Enter the symbol's quoting decimals (integer 0–12): indices usually 0, gold/oil/yen pairs 2, silver 3, major forex 4 — pip size = 10^-decimals, computed automatically.
Decimal places and contract sizes are typical defaults and editable. Most reliable: in MT5, right-click the symbol → Specification, then enter the exact values.
Suggested size
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Exact size
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Pip value / lot
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Risk amount
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Actual risk (rounded)
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How to use it
- Pick a symbol: the dropdown comes with common presets (pip size and contract size pre-filled with typical defaults), or choose "Custom" to enter your own;
- Enter your account size and risk per trade: as a percentage (e.g. 1%) or a fixed amount;
- Enter the stop-loss in pips: how far your stop sits from the entry price;
- Pick the account currency: when the quote currency differs from your account currency, enter a current exchange rate as prompted;
- Read the result: the suggested lot size is rounded down to two decimals, and the actual risk after rounding is shown.
The formula
The calculation has three steps: convert the risk percentage into money, find what one pip is worth per lot, then connect the two with your stop distance.
The exchange rate is entered as "1 account currency = ? quote currency" (e.g. with a USD account and USDJPY, enter 153.62). The result is rounded DOWN to two decimals — rounding up would let the actual risk exceed your planned percentage.
Worked example
The most common setup, as an example: a USD account trading EURUSD.
- Account 10,000 USD, risk 1% per trade → risk amount = 100 USD;
- EURUSD pip size 0.0001, contract size 100,000 → pip value per lot = 0.0001 × 100,000 = 10 USD;
- Stop-loss 50 pips → 50 × 10 = 500 USD risked per lot;
- Position size = 100 ÷ 500 = 0.2 lots.
With 0.2 lots and a 50-pip stop, the worst case for this trade is a 100 USD loss — exactly 1% of the account.
FAQ
Q How much should I risk per trade?
A widely used convention is 1%–2% per trade: even several consecutive stop-outs leave the account intact and your decisions unemotional. The right number depends on your own strategy and tolerance — this tool only converts your percentage into lots and does not constitute investment advice.
Q Why is the suggested size rounded down?
Lot precision is limited by your broker's minimum step (usually 0.01). Rounding to the nearest can push the actual risk slightly above plan, so this tool always rounds down and shows both the exact size and the actual risk after rounding, letting you decide.
Q What are the pip size and contract size for gold, oil or indices?
They vary meaningfully between brokers (gold pip conventions differ — 0.01 vs 0.1; index CFDs map one lot to different index units). Presets use typical defaults and become editable once you pick a symbol — the reliable way is to check your MT5 symbol specification window (right-click the symbol → Specification) and enter the exact values.
Q Why is an exchange rate needed sometimes?
The pip value is first computed in the quote currency (e.g. USDJPY pip values are in yen). Converting it to your account currency needs a current rate. This tool does not fetch prices online — you enter the rate as prompted (format: 1 account currency = ? quote currency), so the result is always based on a price you accept.
Q Does the result guarantee profitable trading?
No. Position sizing only limits how much a single loss can take from your account; it predicts nothing about direction and guarantees nothing. Stops can slip or gap through, and the realized loss may exceed the calculated value.
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Download Camovia TrayResults are for reference only and do not constitute investment advice. Preset pip and contract sizes are typical defaults — the values at your broker and platform prevail; spreads, gaps and slippage may cause actual results to differ.