Calculators

Quick math for traders. Free, no sign-up.

The same nine calculators that live in the Growstones app — percentages, compound growth, risk/reward and more. Results update as you type.

Part of a wholeFind what percentage one number is of another. Enter the part and the whole — the result updates as you type. Percent of an amountCalculate a percentage of any number. Enter the percent and the amount to get the result instantly. Percent changeCalculate the percentage increase or decrease between a starting and an ending value. Add a percentIncrease an amount by a percentage. Enter the amount and the percent to add. Subtract a percentDecrease an amount by a percentage. Enter the amount and the percent to subtract. Compound percentSee how capital compounds when the same percentage is gained every cycle. Enter starting capital, % per cycle and number of cycles. Risk / reward ratioCalculate the risk-to-reward ratio of a trade from the amount at risk and the potential reward. Points to moneyConvert a price move in points into money, using the value of one point for your instrument and position size. ProportionSolve a simple proportion (rule of three): if A corresponds to B, find what corresponds to C.

All nine calculators are also in the Growstones app for iPhone and Android — alongside position sizing, a growth simulator and a weekly journal. Your data stays in your iCloud.

Free for iPhone — on the App Store Free for Android — on Google Play