Crypto Position Size Calculator (Risk-Based, Fees Included)
Decide how much you are willing to lose if the stop-loss is hit, then let the calculator size the position. The calculation runs in your browser.
Position
Position size (notional)
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Amount at risk
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Quantity
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Margin at this leverage
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Distance to stop
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Estimated liquidation price
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At this leverage the estimated liquidation price is reached before your stop-loss. Lower the leverage or move the stop.
How the position size is calculated
Fix the loss first, then solve for the size. At the stop the trade loses the price move plus the opening and closing fees, so all three go in the denominator:
Amount at risk = balance × risk %
Long: quantity = risk ÷ ((entry − stop) + entry × opening fee + stop × closing fee)
Short: quantity = risk ÷ ((stop − entry) + entry × opening fee + stop × closing fee)
Position size = quantity × entry Margin = position size ÷ leverage
Leverage does not change the position size here. It only changes how much margin the position ties up, and how close the liquidation price sits to your entry.
Worked examples (balance 2,000 USDT, risk 1.5%, long at 3,000, OKX taker both ways, 3x)
| Stop-loss | Position size (USDT) | Quantity | Margin at 3x (USDT) |
|---|---|---|---|
| 2,970 (−1%) | 2,728.51 | 0.90950 | 909.50 |
| 2,940 (−2%) | 1,429.25 | 0.47642 | 476.42 |
| 2,910 (−3%) | 968.21 | 0.32274 | 322.74 |
| 2,850 (−5%) | 588.52 | 0.19617 | 196.17 |
How much to risk per trade
- Pick a share of the balance you can lose many times in a row. With 1% per trade, ten losses in a row cost about 10% of the account; with 5%, they cost about 40%.
- Place the stop where the trade idea is wrong, then size. Moving the stop closer just to get a bigger position raises the chance of being stopped out by normal price noise.
- Check liquidation after sizing. If the liquidation price sits before the stop, the stop never protects you. Lower the leverage until the warning disappears, or confirm with the liquidation price calculator.
Frequently asked questions
How do I calculate position size in crypto?
Multiply your balance by the share you are willing to lose to get the amount at risk, then divide it by the loss per coin at your stop, including fees. Position size is that quantity times the entry price.
Does leverage change the position size?
Not in risk-based sizing. The size comes from the amount at risk and the stop distance. Leverage only sets the margin the position uses and how close liquidation is.
What risk percentage should I use?
Many traders keep each trade small enough that a long losing streak does not empty the account, often 1-2% of the balance. It is a personal choice; the calculator shows the size for whatever you enter.
Why is my real loss larger than the amount at risk?
Stop orders can fill below the stop price in a fast market (slippage), funding may be paid while you hold, and a liquidation before the stop loses the margin instead.
Sources and limits
Fee pages: OKX, Bybit, MEXC, checked 2026-11-14. The liquidation estimate uses the isolated-margin formulas of our liquidation calculator with the maintenance margin rate you enter. Planning tool, not trading advice. Leveraged futures can lose the whole margin.