Future value of any asset growing at a steady annual rate.

100,000 compounding at 6% a year for 20 years reaches 320,714 — triple the starting value, with over 220,000 of pure compound growth. Shift the rate to 4% and the endpoint drops to 219,112; at 8% it reaches 466,096. Small rate differences compound into large cash gaps over long horizons.

How to use it

Enter current value, expected annual growth rate, and years. Works for any asset that compounds — a portfolio, property value, a business stake — as long as your rate assumption is realistic for that asset class.

What the result means

Primary is future value. Secondary shows compound growth in cash, doubling time (years needed to double at that rate), and the final multiple on current value.

Rate assumptions by asset class

Cash savings: 2-4%. Government bonds: 3-5%. Global equity index (long-term nominal): 5-8%. Property (long-term nominal): 3-6%. Individual stocks and venture: wildly variable. Use conservative assumptions for anything over 15 years — the longer the horizon, the more the rate matters.

Quick example

With current value of 100,000 and annual growth rate of 6% (plus years of 20 years), the result is 320,713.55. Change any figure and watch the output shift — it's often more useful to see the pattern than to memorise the formula.

Which inputs matter most

You enter Current Value, Annual Growth Rate, and Years. The rate and the time horizon usually dominate — compounding means a small change in either reshapes the final figure more than a similar shift in contribution size. Test this by doubling one input at a time.

What's happening under the hood

Compound growth formula with annual compounding. No contributions — this is the projection of the existing asset alone. Doubling time computed via the Rule of 72 (72 / rate) as a quick approximation. The formula is listed in full below. If the number looks off, you can retrace the calculation by hand — that's the point of showing the working.

Why investors run this

Most people's intuition for compounding is wrong — not because the math is hard, but because linear thinking doesn't account for curves. Running numbers through a calculator like this one is the cheapest way to recalibrate that intuition before making an irreversible decision about contribution rate, asset mix, or retirement age.

What this doesn't capture

Steady-rate math ignores real-world volatility. Actual returns are lumpy; sequence-of-returns risk matters most in drawdown; fees and taxes drag on compound growth; and behaviour changes in drawdowns can reduce outcomes below the projection. Treat the number as one scenario, not a forecast.