Crypto Position Size & Risk Calculator

How to use the position size calculator

Type your account balance and the share of it you are prepared to lose on this trade. Enter the planned entry price and the stop-loss: if the stop is below the entry, the calculator treats the trade as a long; if it is above, as a short. Add a take-profit to see the reward-to-risk ratio, your leverage to see the margin required, and the fee per side charged by your exchange.

The result is the number of coins (or contracts in coin terms) to buy or sell. On futures exchanges that size positions in USDT, use the “position value” figure instead.

The formula

Risk is defined by the distance to the stop, not by the leverage. Leverage only changes how much margin you lock up.

Example

Balance $5,000, risk 1% ($50). Long BTC at $65,000 with a stop at $63,000 (3.08% away) and 0.05% fees per side. The position size is about 0.0242 BTC — roughly $1,575 of exposure. At 5x leverage that needs about $315 of margin. If the stop is hit you lose $50 including fees; at a take-profit of $71,000 you make about $144, a reward-to-risk of 2.87 : 1.

Notice what leverage does and does not change. At 1x or at 20x, the position size for a $50 risk is the same 0.0242 BTC — only the margin changes. Traders who size by leverage (“I’ll use 20x on my whole balance”) take on a far larger risk than they realise.

Rules of thumb for risk management

None of these guarantee profit, but they keep a losing streak survivable:

• Risk a fixed small percentage per trade. Ten losses in a row at 1% leave you with about 90% of the account; at 10% they leave about 35%.
• Place the stop where the trade idea is invalidated, then size the position — never move the stop to fit a bigger size.
• Aim for reward-to-risk of at least 1.5–2 : 1, so that you can be wrong more often than right and still break even.
• Check that your liquidation price is well beyond the stop-loss; use the Liquidation Price Calculator.
• Include fees. On tight stops, fees can be a large share of the risk.

Spot traders can use it too

Position sizing is not only for futures. If you buy spot crypto and keep a mental or exchange stop-loss, the same math tells you how much to buy so that a stop costs you a known amount. Set leverage to 1 and the margin equals the position value — the amount of USDT you need for the purchase.

Glossary

Thinking in R multiples makes results comparable across trades of different sizes: a +3R winner and a −1R loser are the same story whether the account is $500 or $50,000.

• Risk per trade — the share of the account you accept to lose if the stop-loss is hit.
• Stop distance — how far the stop is from the entry, in percent; together with risk it defines the size.
• Position value (notional) — size × entry price; this is what moves with the market.
• Margin — the collateral locked for a leveraged position: notional ÷ leverage.
• R multiple — profit or loss expressed in units of the initial risk; +2R means you made twice what you risked.
• Fee per side — the commission charged on entry and again on exit, as a percentage of notional.