How to size a position in crypto futures

To size a crypto futures position, decide how much money you are willing to lose on the trade, then divide that amount by the distance between your entry and your stop. The result is the position size in coins; multiplied by the entry price, it gives the notional value in USDT.

Leverage does not appear in that calculation. It only decides how much margin the position ties up, which is why sizing by risk rather than by leverage is the habit that keeps losses predictable. The steps below walk through the method with one worked example.

Step 1: decide your risk per trade

Your risk per trade is the amount you lose if the trade hits its stop. Express it as a share of your account, a common rule of thumb being 0.5% to 2%, and convert it into dollars before you look at the chart again.

Example: 1% of a 10,000 USDT account is 100 USDT.

Step 2: measure the stop distance

Place the stop where your trade idea is proven wrong, not where it happens to give you a convenient size. The stop distance is the gap between the entry price and the stop price.

Example: a long on BTCUSDT at 60,000 with a stop at 59,400 has a stop distance of 600 USDT per coin, or 1% of the entry price.

Step 3: calculate the size

Position size = risk amount ÷ stop distance.

In the example: 100 ÷ 600 = 0.1667 BTC. At an entry of 60,000, that is a notional value of about 10,000 USDT. If the stop is hit, the loss is about 100 USDT, which is 1% of the account, as planned.

Notice what happens when the stop moves. A tighter stop allows a larger position for the same risk, and a wider stop forces a smaller one. The amount at risk stays fixed; the size adapts to the trade.

Where leverage fits in

Leverage sets the margin the exchange holds for the position: margin = notional ÷ leverage. At 5x, the 10,000 USDT position above needs about 2,000 USDT of margin; at 10x, about 1,000 USDT.

What leverage does not change is the loss at your stop, which is fixed by the size and the stop distance. What it does change is how close the liquidation price sits to your entry: the less margin behind a position, the smaller the adverse move it can absorb. Keep the liquidation price well beyond your stop, and if the margin the trade needs is more than you are comfortable committing, reduce the size instead of raising the leverage.

Fees, funding and slippage

The formula gives the loss at the exact stop price. Real losses are a little larger: you pay trading fees on entry and on exit, funding payments may go against you while the position is open, and a stop-market exit can fill beyond the stop in a fast market. Leave a buffer, for example by sizing for slightly less than your full risk amount.

A quick checklist

• The risk amount is decided in dollars before the trade.
• The stop is placed where the idea is wrong, then measured.
• Size = risk ÷ stop distance, rounded down to the exchange's quantity step.
• Margin and liquidation price are checked against your account.
• There is room left for fees, funding and slippage.

Try it with the calculator

Our free position size calculator does this arithmetic in your browser. Enter your balance, risk, entry, stop and leverage, and it shows the size, the notional value, the margin and, if you add a target, the risk-reward and the result at the target. Nothing you type is sent anywhere.

How Mos Terminal helps

Mos Terminal lets you save your own order sizes for one-click orders, caps the size of a single order and your total open size before anything reaches the exchange, and backs every position with a server-side hard stop in case a trade goes further than you planned.

Key takeaways

• Size = risk amount ÷ stop distance; notional = size × entry price.
• Decide the risk in dollars before you think about leverage.
• Leverage changes the margin and the distance to liquidation, not the loss at your stop.
• A wider stop means a smaller position for the same risk.
• Leave room for fees, funding and slippage.

Mos Terminal enforces a hard stop and a day breaker on our server for Binance USDⓈ-M futures, so your limits hold even with the browser closed. It is in invite-only beta.

Educational content, not financial advice. Futures trading carries a high risk of loss.