How the position size is calculated
Position sizing starts from the loss you accept if the stop is hit, not from the size you would like to trade. The calculator multiplies the account size by your risk per trade to get the dollar risk, then divides that by the distance between entry and stop to get the quantity. Quantity × entry is the notional value of the position, and notional ÷ balance is the leverage the trade really uses.
Example: on a $50K QATS Crypto account, 0.5% risk is $250. A BTC long at 65,000 with a stop at 64,350 has a 650 distance (1%), so the size is 0.3846 BTC — about $25,000 notional, or 0.5× leverage.
Leverage caps by instrument tier
QATS Crypto measures capacity as notional: balance × leverage for the instrument’s tier — 20× on BTC and ETH, 10× on large caps and 5× on other coins. The tighter the stop, the larger the quantity for the same dollar risk, so on a very tight stop the cap — not your risk — becomes the limit.
When that happens the calculator flags it and shows two ways out: the largest risk the cap allows with your stop, and the narrowest stop distance that lets you keep your chosen risk.
How many losses fit before the limits
The bar under the results stacks one block per full loss against the plan’s limits. On QATS Crypto the daily loss limit is 4% of the starting balance and reaching it fails the account; the maximum loss is 6%, trailing at the end of each day until it reaches the starting balance. At 0.5% risk on $50K that is 8 losses before the daily limit and 12 before the maximum loss.
The count assumes a fresh account at its starting balance. After profitable days the trailing floor rises, so the room to the maximum loss shrinks unless the floor has already locked at the starting balance.
Assumptions and how to use it
Results update as you type. The stop distance is measured from the entry price you enter; fills, commissions, funding payments and slippage past the stop are not included, and a fast market can gap through any stop. Use the numbers to plan a trade, then confirm the order ticket in the terminal before you send it.
Frequently asked questions
How do I calculate position size for a prop firm account?
Multiply the account size by the risk per trade to get the dollar risk, then divide it by the distance between entry and stop. The result is the quantity; quantity × entry is the notional value of the position.
What risk per trade should I use on a funded account?
That is your decision. Many traders size so that a normal losing streak cannot reach the daily loss limit: on a QATS $50K Crypto account, $250 per trade (0.5%) allows 8 full losses before the 4% daily limit.
Why does the calculator warn about leverage?
A very tight stop makes the quantity large. QATS Crypto caps notional at 20× the balance on BTC and ETH, 10× on large caps and 5× on other coins, so the calculator shows when the size would exceed that cap and the widest risk the cap allows.
Does the calculator include fees and slippage?
No. Commissions, funding and slippage past the stop all add to a real loss, so leave a buffer below the limits rather than sizing to the exact number.