Free Tool
Compound Growth Calculator
Small growth, repeated, becomes large: that is compounding. Enter a starting value, a growth rate per period and the number of periods, and this calculator shows the end value and how it grows, period by period.
Estimates and scenarios for planning purposes only — not financial advice. The results on this page are built from the numbers you enter. They are planning aids, not predictions, and not financial, tax or legal advice. Nothing you enter leaves your browser.
What this tool does
The formula is end value = starting value × (1 + rate)^periods. With a starting value of 1,000, a 5% rate and 10 periods, the end value is 1,000 × 1.05^10 = 1,628.89. The table shows each period's value, so you can see the growth itself growing: the gain in period 10 is larger than the gain in period 1, because the rate applies to a larger amount each time. That is the whole idea of compounding — growth on growth.
Rates are entered per period, and a period is whatever you decide it is: a month, a quarter, a year. The calculator does not know, and does not assume — a 5% monthly rate is very different from a 5% yearly one, so the meaning of the answer depends entirely on what you mean by a period. No 'expected return' for any asset is suggested or stated.
Try it
Waiting. Enter a starting value, rate and periods and press Calculate growth.
How it works
End value = starting value × (1 + rate)^periods, with the rate entered as a percentage and converted to a decimal. The table value for period n is the same formula with n in place of the total periods: starting value × (1 + rate)^n. When the periods are more than 24, the table shows every twelfth period plus the final one, instead of all of them.
The same formula works for money, subscribers, traffic or any quantity that grows by a percentage each period — the maths does not care what is growing. What changes is the meaning of 'rate' and 'period', and those are set by you.
Assumptions and limitations
- Nothing here suggests an 'expected return' for any asset, audience or business. A rate you enter is an assumption, and the result shows what that assumption implies — not what will happen. Past growth does not guarantee future growth, in any domain this formula is applied to.
- The rate is held constant, period after period. Real growth varies: it speeds up, slows down, sometimes reverses. A single steady rate is a model, not a description of reality.
- The calculator assumes growth compounds — each period's growth is calculated on the new, larger value. Simple (non-compounding) growth would give a smaller end value; the two are different, and this tool calculates the compound one.
Worked example
Example: starting value 1,000, growth 5% per period, 10 periods. End value = 1,000 × 1.05^10 = 1,628.89. Total growth = 628.89. Period 1 is 1,050.00 and period 5 is 1,276.28 — the gain per period grows as the value grows.
Frequently asked questions
What is the difference between compound and simple growth?
Simple growth adds the same amount every period (5% of the starting value, each time). Compound growth adds 5% of the current value, so the gain grows as the value grows. Over 10 periods at 5%, simple growth gives 1,500; compound growth gives 1,628.89.
What is a period?
Whatever you decide: a month, a quarter, a year. The calculator does not know. A 5% monthly rate and a 5% yearly rate give wildly different answers, so be clear — with yourself, at least — which one you mean.
Can the rate be negative?
Yes, down to −99%. A negative rate models decline: the value shrinks by that percentage each period. Below −100% the value would go negative, which has no meaning here, so the calculator stops at −99%.
Does this predict investment returns?
No. It shows what a rate you enter implies over the periods you enter. It says nothing about what any investment, audience or business will actually do.
How is this different from the revenue forecast?
The formula is the same compounding. The forecast applies it to three scenarios at once (base, optimistic, pessimistic) for revenue; this calculator applies it to one value, one rate, and shows the period-by-period table.