Tools · T-02

Position size calculator

Last checked: July 2026

Line illustration of a ruler measuring the gap between an entry price line and a stop-loss line

Decide how much you can lose first. This works backward from that number to tell you how big the position should be.

Account size (USDT)

Risk per trade (%)

Entry price

Stop-loss price

—

position size, in units of the asset you're buying

—notional value (USDT)

—amount at risk if stop is hit

—stop distance (%)

The math: your risk amount is a fixed slice of your account (risk % × account size). Divide that by the gap between entry and stop, and the result is how many units you can hold so that if the stop is hit, you lose exactly the risk amount — no more. A tighter stop means a bigger position for the same risk; a wider stop means a smaller one. Position size moves to keep risk constant, not the other way around.

This calculator doesn't know your leverage, your fees, or slippage — it's the base risk math. On a leveraged position the same risk-amount logic applies, but check your exchange's own margin and liquidation-price tools before sizing a leveraged trade, since liquidation can happen before your stop order fills.

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What does "risk per trade" actually mean here?

It's the maximum dollar amount you're willing to lose on this one trade if your stop-loss is hit, expressed as a percentage of your total account. A common starting point is 1% or less per trade, so a string of losses doesn't do lasting damage to the account.

How do I use this before placing an order?

Decide your entry and stop first, based on your own analysis — this tool doesn't pick those for you. Then enter them along with your account size and risk tolerance, and use the resulting position size (or notional value) as the order size, not a number you eyeballed.

Common mistake: sizing by "how much I want to make" instead of risk

Sizing a position based on a profit target ("I want $500 back") ignores how much you're risking to get there and tends to produce oversized positions. Sizing by fixed risk keeps every trade's downside comparable, regardless of how confident you feel about it.

Does this account for leverage or fees?

No — this is the base risk-sizing math on the price gap alone. On leveraged positions, check your exchange's margin and liquidation-price calculator too, since a liquidation can trigger before your stop-loss order fills, especially in fast markets.