Comparison
Free position size calculators against ZRisk
A free calculator gives you a number. What is missing from that number, why it matters on futures, and when free is genuinely the right answer.
The short version
Free calculators solve the arithmetic, which was never the hard part. On futures the hard part is everything the arithmetic leaves out: the fees on both legs, the funding while you hold, the lot rules of the pair, and the fact that the price has moved since you loaded the page.
| a free online calculator | ZRisk | |
|---|---|---|
| The core formula | Correct | Correct |
| Price | Typed in by you | Live from the exchange |
| Entry and exit fees | Ignored | Inside the size |
| Funding | Ignored | Estimated for your holding time |
| Lot step, minimum quantity, minimum value | Ignored | Read per pair |
| Liquidation checked against your stop | No | Yes, and ordering is blocked if it would come first |
| Places the order | No | Yes, with stop and target attached |
| Price | Free | Free calculator too, ZRisk for the rest |
The number is right and the trade is still wrong
Risk over stop distance gives a quantity. On a futures exchange that quantity then has to survive the lot step, the minimum order value and your leverage, and it has to be paid for twice in commission. A calculator that stops at the formula hands you a number you still have to correct by hand.
Fees are small and they are also the whole edge
A round trip at the standard taker rate is a tenth of a percent of position value. That sounds like nothing until it is set against the edge of a strategy that wins slightly more than half the time. The size should carry that cost, not discover it afterwards.
We give away a free one as well
There is a free risk and reward calculator on this site with no account and no sign-up, and free tools for fees, funding and liquidation. Use them for as long as they are enough.
Questions
Yes, and it needs no account. The paid product is the live, fee-accurate version connected to your exchange.
Because the loss you actually take at your stop is the price loss plus the commission on the way in and the way out. If the size is set from the price loss alone, a stop-out costs more than the risk you set.
Try it on your next trade
The free calculator needs no account. Size a trade with it and see whether the difference is real for you.