Lot Size Calculator Forex
Estimate lots from your chosen risk budget and stop distance. Verify the pip value in your account currency; this page does not fetch exchange rates or recommend a trade.
One standard lot = 100,000 base units; pair pip size 0.0001. Quote currency: USD. Same-currency default uses these units; otherwise supply the current converted broker value. No live conversion.
Raw lots: 0.200000. Modeled loss at stop after rounding: $100.00. Check broker minimum/maximum size and margin separately. Fees, spread, slippage and conversion changes are excluded.
Alternative Lot Sizes
Hypothetical Gross P&L Scenarios
Match the units before dividing
Risk budget = account balance × chosen percentage. Raw standard lots = risk budget / (stop distance in pips × pip value per standard lot in account currency). This page assumes a standard lot of 100,000 base units. Mini and micro lots represent the same exposure in different units.
For EUR/USD with a USD account and pip size 0.0001, one standard lot moves $10 per pip. For USD/JPY, a 0.01 pip represents 1,000 JPY per standard lot; a USD account needs that amount converted at the applicable rate. The pair selector does not obtain a quote or infer a conversion rate.
Rounding changes the modeled risk
A hypothetical $10,000 account, 2% budget, 30-pip stop and $10 pip value gives 0.666666… standard lots. With a 0.01-lot step, round down to 0.66 lots: the modeled stop loss is $198 before costs. Rounding to 0.67 instead would model $201, above the $200 budget.
What the estimate leaves out
The chosen risk percentage is your assumption, not an endorsement. A stop is not a guaranteed fill, and correlated positions can increase account-wide exposure. Spread, commission, slippage, gaps, conversion changes and financing can affect realized P&L. Margin requirements and broker minimum size may prevent trading the displayed amount.
Hypothetical P&L scenarios multiply the rounded position’s modeled risk by a price-distance ratio. They are neither forecasts nor expected returns. A consistent sizing formula does not imply a consistent equity curve or protection from large drawdowns.
Sources
- OANDA: units and lot conventions
- IG: forex contract specifications and currency treatment
- IG: normal stops and execution
Frequently Asked Questions
Where does the pip value come from?
No exchange rates are fetched. If the account currency equals the pair’s quote currency, the default is 100,000 × pip size in that currency. Otherwise enter the current broker pip value for one standard lot in your account currency. Changing pair or currency clears values that require conversion.
Why is the result rounded down?
The raw position is rounded down to your entered lot step. This avoids rounding above the modeled budget, but does not account for fees, slippage or changing conversion rates. Check the broker’s separate minimum and maximum size and margin requirements.
Does the risk amount cap my actual loss?
No. It is stop distance times pip value times modeled lots. Gaps, slippage, spreads, fees and execution failures can produce a different loss. Position sizing cannot guarantee account preservation or consistent returns.
Are the risk-reward scenarios predictions?
No. They show hypothetical price distances and gross P&L multiples for the rounded position. They say nothing about hit probability, trading edge or whether an order will fill.
Build and Review Trading Rules
Pineify can help draft Pine Script indicators and strategies. Verify contract units and sizing logic in TradingView. Generated code and alerts do not by themselves connect to a broker or guarantee risk limits.
Explore Pineify