Position size calculator
Size a spot or linear futures position from a stop price and a loss budget.
Inputs
The starting values are a hypothetical example. Replace them with your own.
Result
Hypothetical example result.
- Position quantity
- 19.2492781521 units
- Entry exposure
- 1,924.9278 quote
- Spot purchase value
- 1,924.9278 quote
- Loss budget
- 100 quote
- Loss if filled exactly at stop, including fees
- 100 quote
- Stop-fill loss as share of balance
- 1 %
- Entry fee cost
- 1.9249 quote
- Stop exit fee cost
- 1.8287 quote
- Net profit if filled at take-profit
- 188.4504 quote
- Net reward / stop-fill loss
- 1.8845 ratio
- Quantity includes entry and stop-exit fees in the loss budget and is capped by available balance. Estimated margin excludes fees.
- Linear futures use quote-currency settlement. Leverage changes margin, not the price-move loss for a fixed quantity.
- Actual fills, lot sizes, funding, margin tiers and venue rules can differ. This calculator does not estimate liquidation or guarantee a stop fill.
Saved scenarios
Save up to 20 named scenarios across the calculators in this browser. These values are not placed in the page URL. Saving needs browser storage; deleting a scenario removes its local copy.
Saved scenarios need JavaScript.
Formula and worked example
Loss budget = balance × risk percent ÷ 100. Loss per unit at the stop = absolute price difference + entry fee per unit + stop-exit fee per unit. Quantity = loss budget ÷ loss per unit, capped by the funds needed for the purchase or estimated margin and entry fee.
Exposure = quantity × entry. Linear futures margin estimate = exposure ÷ leverage. The loss at the stop depends on price movement and quantity, even when leverage reduces the initial margin.
Hypothetical example: balance 10,000, risk 1%, entry 100, stop 95, and 0.1% fees on each side. The 100-unit loss budget allows about 19.2493 units. Entry exposure is about 1,924.93, and loss at an exact stop fill is 100 including fees.
Related reading
This website is developed by Zack White and Vincent Hale.