CAGR Formula Calculator & Step-by-Step Guide

This CAGR formula calculator works out the Compound Annual Growth Rate from a starting value, an ending value, and the number of years (or periods) in between. You enter those three numbers, and you get back the annual growth rate that would turn the start value into the end value over that time, assuming steady compounding. The result is shown as a percentage, and the calculator also gives you the total growth and the growth factor, so you can see how the numbers connect.

Formula

The CAGR formula is:

CAGR = (Ending Value / Starting Value)^{(1 / Number of Years)} − 1

In words: divide the ending value by the starting value, raise that result to the power of one divided by the number of years, then subtract one. The answer is a decimal; multiply by 100 to get a percentage.

Variables:

• Starting Value – the initial amount (in any currency or unit, as long as it matches the ending value).
• Ending Value – the final amount after the period.
• Number of Years – the time span in years. It can be a decimal (e.g., 3.5 for three and a half years).
• CAGR – the compound annual growth rate, expressed as a percentage per year.

The formula assumes that growth happens smoothly and compounds at the same rate every year. It does not care about what happened in between – only the start and end points matter.

Worked Example

Using the default values from the calculator: starting value = 1,000, ending value = 2,500, number of years = 5.

1. Divide the ending value by the starting value: 2,500 ÷ 1,000 = 2.5
2. Raise 2.5 to the power of 1/5 (which is 0.2): 2.5^0.2 ≈ 1.2011
3. Subtract 1: 1.2011 − 1 = 0.2011
4. Convert to a percentage: 0.2011 × 100 = 20.11%

So the CAGR is about 20.11% per year. That means if you invested $1,000 and it grew at a steady 20.11% each year, after 5 years you would have $2,500.

Check: 1,000 × 1.2011⁵ = 1,000 × 2.5 = 2,500. The math works out.

When to Use CAGR

CAGR is most useful for comparing the growth of investments, revenue, user counts, or any metric that changes over time. It smooths out volatility, so you can compare a bumpy ride (like a stock that swings wildly) with a steady one on the same footing.

Common uses:

• Comparing the historical performance of different investments.
• Measuring the growth of a company’s revenue over several years.
• Projecting future values if you assume the same growth rate continues (though that is a big “if”).
• Benchmarking against an index or a target.

Because CAGR only looks at the start and end values, it is ideal for situations where you care about the overall result, not the path taken to get there.

How to Read the Result

The CAGR percentage tells you the annual rate at which the value would have to grow, every year, to go from the start to the end value. A higher CAGR means faster growth. However, it is not the same as the average annual return.

For example, if an investment goes from $100 to $50 in year one (−50%) and then to $100 in year two (+100%), the average annual return is (−50 + 100)/2 = 25%, but the CAGR is 0% because you ended up where you started. CAGR is the more honest measure of actual growth.

Also note that CAGR is an annualized figure. If your period is less than a year, the calculator still works, but the result will be an annualized rate, which can be misleading for short periods (e.g., a 10% gain in one month annualizes to about 213% – which is not a realistic expectation for the future).

Common Mistakes and Pitfalls

Here are the most frequent errors people make when calculating CAGR:

• Unit mix-ups: Make sure the starting and ending values are in the same units (both in dollars, both in thousands, etc.). If you mix, the result is meaningless.
• Using the wrong number of periods: If you have data for 5 years, the number of years is 5, not 4. If you have quarterly data, you need to convert to years (e.g., 8 quarters = 2 years).
• Forgetting to subtract 1: The formula is (End/Start)^(1/n) − 1, not just (End/Start)^(1/n). That subtraction is what turns a growth factor into a growth rate.
• Confusing CAGR with simple average: As shown above, the arithmetic average of annual returns is not the same as CAGR.
• Rounding too early: If you round intermediate steps, you can get a noticeably different final answer. Keep full precision until the end.

Limitations of CAGR

CAGR is a useful summary, but it has limits:

• It ignores volatility: Two investments with the same CAGR can have very different risk profiles. One might grow steadily, the other might have huge swings.
• It assumes smooth growth: Real-world growth is rarely steady. CAGR is a geometric average, not a reflection of actual yearly returns.
• It is backward-looking: Past CAGR does not guarantee future results. Using it to project forward is an assumption, not a fact.
• It can be misleading for negative or zero start values: If the starting value is zero or negative, the formula breaks down (division by zero or negative roots). The calculator requires a positive start value for that reason.

For investments with cash flows in and out (like contributions to a retirement account), CAGR is not the right tool – you would need an internal rate of return (IRR) calculation instead.

How to Calculate CAGR in a Spreadsheet

If you are using Excel, Google Sheets, or similar, the formula is:

=((End/Start)^(1/Years))-1

For example, if your starting value is in cell A1, ending value in B1, and years in C1, the formula would be:

=((B1/A1)^(1/C1))-1

Format the cell as a percentage to see the result as a percentage. Many spreadsheets also have a built-in RRI function (e.g., =RRI(C1, A1, B1)) that does the same thing, but the manual formula works everywhere.

Frequently Asked Questions

What is the difference between CAGR and average annual return?

The average annual return is the simple arithmetic mean of yearly returns. CAGR is the geometric mean, which accounts for compounding. For example, a 50% loss followed by a 100% gain gives an average annual return of 25%, but the CAGR is 0% because you ended up with the same amount you started with. CAGR is a more accurate measure of actual growth over time.

Can CAGR be negative?

Yes. If the ending value is less than the starting value, the CAGR is negative, meaning the value declined on average each year. For instance, $1,000 dropping to $800 over 3 years gives a CAGR of about −7.17% per year. The calculator will show a negative percentage in that case.

How do I calculate CAGR for monthly or quarterly data?

First, determine the total number of years. For monthly data, divide the number of months by 12. For quarterly data, divide by 4. Then use that decimal number of years in the formula. For example, 18 months = 1.5 years. The CAGR will be annualized, meaning it represents the yearly growth rate that would produce the same result over that period.

What if my starting value is zero or negative?

The CAGR formula requires a positive starting value. If the starting value is zero, the ratio End/Start is undefined (division by zero). If it is negative, the root may be undefined for fractional exponents. In those cases, CAGR is not a meaningful measure. You might consider using a different metric, like the total growth in absolute terms, or the internal rate of return if there are cash flows.

Is CAGR the same as annualized return?

Yes, in most contexts, “CAGR” and “annualized return” are used interchangeably. Both refer to the geometric average annual growth rate over a period. Some people use “annualized return” for investments with cash flows, but when it is just a start and end value, they are the same.

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in start | Starting value | - | 1000 | 0
in end | Ending value | - | 2500 | 0
in years | Number of years | - | 5 | 0
out cagr | CAGR | % | ((end / start) ^ (1 / years) - 1) * 100 | 2
out total | Total growth | % | (end / start - 1) * 100 | 2
out factor | Growth factor | - | end / start | 2