Position Size Calculator
Find the exact number of units to trade so a stop-out costs you only what you decided to risk — no more.
Your position
Free, no sign-up, nothing leaves your browser — all math runs locally.
How to calculate position size
Position sizing answers the only risk question that matters before you click buy: how many units can I trade so that, if my stop is hit, I lose no more than my predetermined risk? The math is simple and the same across stocks, forex, crypto, and futures:
So on a $25,000.00 account risking 1% with a $2.00 gap between entry and stop, you'd take 125 units. Widen your stop and the position shrinks; tighten it and the position grows — but your dollar risk stays fixed. That's the whole point: the stop defines the size, not the other way around.
Why fixed-fractional risk wins
Risking a constant small fraction (the classic 1–2%) means no single trade can seriously dent your account, and a losing streak shrinks your bet size automatically — you risk less in dollar terms precisely when you're cold. It's the simplest defense against the one thing that ends trading careers: a position so large that being wrong is unrecoverable.
The calculator flags any trade above 2% account risk. If you're consistently reaching for more, the problem usually isn't the position size — it's a stop placed too tight for the setup, forcing you to size up to make the trade "worth it." A journal that tracks your actual risk per trade over time (TradeInsights does this automatically) is how you catch that pattern before it compounds.
Frequently asked questions
How does a position size calculator work?
It divides the dollar amount you're willing to risk (account balance × risk %) by the per-unit risk (the distance between your entry and stop-loss). The result is the largest position that keeps your loss within budget if the stop is hit.
How much should I risk per trade?
Most professional traders risk 1–2% of account equity per trade. At 1%, you can lose 20 trades in a row and still have ~82% of your account; at 5%, the same streak nearly halves it. Smaller, consistent risk is what survives variance.
Does this work for forex and crypto, not just stocks?
Yes. The entry-minus-stop method is universal — it sizes in 'units,' which are shares for stocks, coins for crypto, or base units for forex. For forex lots, divide the unit result by your contract size (e.g. 100,000 for a standard lot).
What is 'implied leverage' in the results?
It's your position value divided by your account balance. A 5× implied leverage means the position controls five times your account — fine for futures/forex, but a flag if you didn't intend to use margin on a stock or spot crypto trade.
Is anything saved or sent anywhere?
No. The entire calculation runs in your browser — nothing is uploaded, stored, or logged. Create a free TradeInsights account only if you want your real trades' position sizing tracked automatically over time.
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