Calculator
Position size calculator
How it works
Position size is the amount you can buy or sell so that a stop-loss loses a fixed share of your account. Divide the money you accept to lose by the price distance to the stop, plus the fees paid on entry and exit. Leverage does not change this size; it only changes the margin the position locks.
Results
Position size (coins)
- Direction
- Long
- Position value
- $4,764.17
- Margin required
- $952.83
- Loss at the stop
- $100.00
- Stop distance
- 2.00%
- Fees, entry and stop
- $4.72
Fill in every field with a number above zero to see the result.
The formula
Pick the most you accept to lose on the trade. The position size is the size at which the stop-loss loses exactly that amount, after the taker fee on entry and the taker fee on the stop.
risk amount = balance × risk % size (coins) = risk amount ÷ (|entry − stop| + fee × (entry + stop)) position value = size × entry margin = position value ÷ leverage
Worked example
You hold $10,000 and risk 1% per trade, so a stop-out may cost $100. You go long at 70,000.00 with a stop at 68,600.00, a distance of $1,400 per coin. With a 0.05% taker fee on each side, the fees add $69.30 per coin.
The size is $100 ÷ $1,469.30 = 0.06806 coins, a position worth $4,764.17. At 5× leverage the exchange locks $952.83 as margin. Without fees the size would be 0.071429 coins, and the stop would lose $4.95 more than planned.
Things the formula leaves out
- Slippage: a stop-market order can fill past the stop price in a fast market.
- Funding: holding a perpetual through funding times adds or removes a little equity.
- Venue limits: each market has a minimum size, a size step and a maximum market order size. Round the result to the market's step before you place the order.
Frequently asked questions
Does leverage change the position size?
No. The stop-loss distance and the money you accept to lose set the size. Leverage only sets how much margin the exchange locks for that size. Higher leverage frees margin but moves the liquidation price closer to entry.
Why include fees in the position size?
A stop-loss usually fills as a market order, so you pay the taker fee twice: once to open and once to close. Without fees the real loss at the stop is larger than the risk you planned.
What risk per trade should I use?
Many traders risk 0.5% to 2% of the account on one trade, so a run of losses does not empty the account. The right number depends on your strategy and is your decision; this calculator only does the arithmetic.
Can slippage make the loss larger than planned?
Yes. In a fast market the stop can fill past the stop price. The calculator assumes a fill at the stop price, so keep some room for slippage on volatile coins.
Results are estimates for planning. Exchanges add fees, funding and tier rules of their own; check the order preview on your venue before you trade. Nothing here is investment advice.
Trade every venue from one tab.
Binance, OKX, Bybit, and Hyperliquid with news, charts, and one-command orders. Included with Ninja Squad Pro membership.