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CAGR Calculator: Compound Annual Growth Rate

Enter the opening value, closing value and elapsed years to calculate a compound annual growth rate. Use cash-flow return methods when money was added or withdrawn during the period.

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Your numbers

Your figures stay on this device.

How the calculation works

CAGR turns a start-to-finish change into one constant annual compound rate. It is suitable for an investment with no intermediate external deposits or withdrawals, even when the actual yearly performance was uneven.

CAGR = (ending value ÷ starting value)^(1 ÷ years) − 1. A zero ending value represents a 100% loss.

  1. Measure the overall growth factor

    Divide closing value by opening value. This captures the cumulative change before spreading it over time.

  2. Find an equivalent annual factor

    Take the growth factor to the power of one divided by elapsed years. This finds the constant annual multiplier that recreates the closing value.

  3. Express growth as a rate

    Subtract one and display the result as a percentage. The separate total-change figure remains cumulative and should not be confused with the annual result.

Worked example: Check Compound annual growth rate

Sample inputs demonstrate the method. They are not a forecast or product offer.

The first example grows from 100 to 121 over two years. An annual factor of 1.10 produces 100 × 1.10 × 1.10 = 121, giving a 10% CAGR rather than half of the 21% total change.

Starting value
100
Ending value
121
Elapsed years
2

Expected result

Compound annual growth rate
10%
Worked example: Check Compound annual growth rate

Sample inputs demonstrate the method. They are not a forecast or product offer.

Starting value
100
Ending value
81
Elapsed years
2

Expected result

Compound annual growth rate
-10%

Understanding your result

The same CAGR can describe very different return paths. It says nothing about the size of temporary losses, volatility or how steadily the investment grew.

When extra money was paid in, a larger closing balance may reflect contributions rather than performance. IRR or XIRR is needed to incorporate those external cash flows and their timing.

Questions you might have

What does the result include?

Annualise the change between a starting and ending value when there are no intermediate deposits or withdrawals.

Which limits should I check?

A smooth annual equivalent does not describe the actual path or volatility.

Choosing the right inputs

Starting value
Use a strictly positive opening value. A zero opening amount provides no meaningful growth-rate denominator.
Ending value
Use the comparable closing value after the same valuation treatment. Zero is permitted and represents a complete loss of the starting value.
Elapsed years
Enter elapsed years, including a fractional year where appropriate. This field does not calculate time from calendar dates.

Common mistakes to avoid

  • Do not divide total percentage growth by years; that ignores compounding.
  • Do not compare values in different currencies without establishing one consistent valuation basis.

Assumptions to check

  • A smooth annual equivalent does not describe the actual path or volatility.
  • All calculations run on your device. Figures are scenarios based on your inputs, not investment recommendations.

Sources and method

Read our calculation and testing approach.