Lot size calculator
Enter your account balance, the amount you would lose if the stop is hit (as a percentage or as an amount), your stop distance, and the value of one point for one lot on your instrument.
The calculator returns the position size in lots, shows the loss at the stop after rounding down to your broker’s lot step, and prints the formula with your own numbers in it so you can redo it by hand. It works for forex pairs, gold, indices and futures, as long as you know the point value your broker uses; the section below shows where to find it. The inputs start blank on purpose. We do not suggest a risk percentage, because that choice is yours. Entries that could be read two ways, such as “1,500” in a field that also accepts decimals, are refused instead of guessed. It runs entirely in your browser and nothing you type is sent anywhere.
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Your numbers
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Where to find the value per point
Your platform’s contract specification lists the contract size and tick value for each symbol. In MT5, right-click the symbol in Market Watch and open Specification. The value per point can differ between brokers for the same symbol name, so use your own broker’s figure, and measure the stop distance in the same points.
- Forex: the value of one pip (or one point, if your platform quotes five decimals) for one standard lot, in your account currency.
- Gold and indices (CFDs): the contract size times the price step, as listed in the specification.
- Futures: the exchange’s multiplier per point for one contract; here a “lot” is one contract.
Questions
How is lot size calculated?
Lot size equals the amount you are prepared to lose divided by the stop distance times the value of one point for one lot. For example, a risk amount of 200 with a 40-point stop and 1 per point per lot gives 5 lots. The page shows this formula filled in with your inputs.
Where do I find the value per point for gold or an index?
Your platform’s contract specification lists the contract size and tick value for each symbol. In MT5, right-click the symbol in Market Watch and open Specification. The value per point can differ between brokers for the same symbol name, so use your own broker’s figure.
What risk percentage do other traders use?
The calculator does not suggest one. How much you risk is your decision, and this page does not recommend any size. It only converts the amount you choose into lots.
Why is the loss at the rounded size lower than what I entered?
Brokers trade in fixed lot steps, often 0.01 lots. If the exact size falls between steps, the page rounds down and shows the loss at the rounded size. If even one step is larger than your risk amount, the page says so instead of rounding up quietly.
Does it include spread, commission or slippage?
No. It sizes from the stop distance you enter. If you want costs included, add the spread to your stop distance; commission and slippage are not modelled.
Related
- Trade stats: what your own trade file shows.
- Prop-firm challenge simulator: replay a challenge from your own trading days.
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