finance/calculator
Position Size Calculator - Free & Instant | Smocky
Total account balance you trade from.
Share of the balance one losing trade may cost; 1–4% is the usual range.
Distance from Entry to your stop, as a percentage of Entry.
Multiple the exchange applies. It changes only what you put in, never the loss at the stop.
Optional — price levels
The price you open at. Everything below needs it.
Where the idea is wrong. Entering it fills in % Stop Loss above.
Optional target, for the R multiple and the gain if it is reached.
Your exchange’s rate for this tier. Used only for the Liquidation estimate.
Fees
What the exchange charges to open, if your order rests on the book.
What it charges to close. A stop order is a taker. Leave both empty to ignore fees.
Frequently asked questions
Does Leverage change my Risk budget?
No. Your Risk budget and the Stop distance set the Notional, and the loss at the stop is the same at every Leverage. Leverage only divides that Notional into the Margin the exchange locks, which is the number this Tool reports.
Why is the result called Position Size when it is the Margin?
The card follows the video it reproduces, where the result row reads Position Size. In this site’s glossary that number is the Margin — the amount an order form in cost mode asks for — while Position size is the coin quantity. The caption under the result says so on screen.
What does “N more losses” mean, and is it the Risk of ruin?
It is the Loss allowance: floor(100 ÷ Risk %) − 1, how many further losses of the same size the balance covers. It is a count, not a probability, and it ignores compounding. For the probability of ruin over a sequence of trades, use the Risk of Ruin Calculator.
Why does the Tool warn once I go above 5%?
Because of what it does to the Loss allowance. At 2% a losing trade leaves 49 more of the same size; at 5% it leaves 19, and at 10% only 9. Nothing is blocked — the slider goes to 100% and the result is still calculated — but a run of losses that a 1–4% share absorbs can end an account sized this way. The warning is about that count, not about a probability; for the probability, use the Risk of Ruin Calculator.
Do the optional prices change my Position Size?
No. They only add rows: the coin quantity to type as the order’s size, the R multiple and gain if the Take Profit is reached, and an isolated-margin Liquidation estimate. One of them does feed back — entering an Entry and a Stop Loss Price fills in % Stop Loss for you, since a stop price and a contradictory stop percentage cannot both be right. Editing the percentage afterwards clears the price.
Why does entering a fee rate make my Position Size smaller?
Because the fees come out of the same Risk budget. Without them the position is sized so the price move to your stop costs exactly your Risk budget — but a real stop also pays the exchange twice, to open and to close, so the trade costs more than you budgeted. With a rate entered the size is solved so that the move plus both fees comes to your Risk budget, which means a slightly smaller position. At 0.02% maker and 0.055% taker on the example figures it is about 2% smaller. Leave both rates empty and nothing changes.