See how a balance snowballs when each period's gains ride on the last. Enter a starting balance, the percent return per period, and how many periods you're modeling, this free calculator shows your ending balance and total growth. Great for sanity-checking "what if I compound X% a month" ideas.
Compounding means each period's return is applied to the new balance, not just your original stake. The formula is ending balance = start × (1 + r)n, where r is the return per period as a decimal (5% = 0.05) and n is the number of periods.
Start with $10,000 at 5% for 12 periods: $10,000 × (1.05)12 ≈ $17,959. That's a total growth of about 79.6%, well above the 60% you'd get from simple (non-compounding) 5%×12 math.
Total growth % = (ending − start) ÷ start × 100. A negative return per period works too, it shows how losses compound the same way gains do.
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Educational tool. Not investment advice. JagSim is a simulator, not a broker.
Last updated: July 2026