CAGR Calculator
Compound annual growth rate between any two values — and because all four numbers determine each other, this CAGR calculator also solves backwards for the ending value, the starting value or the number of years.
Free · No signup · Runs entirely in your browser
Compound annual growth rate is the single rate that would take the starting value to the ending value if it grew by the same percentage every year. Fill in three of the four and this CAGR calculator solves for the one you left out.
What it was worth at the beginning.
What it is worth now.
Length of the period. Decimals are fine.
| Year | Value | Gain that year |
|---|---|---|
| Start | $10,000 | — |
| 1 | $12,011 | $2,011 |
| 2 | $14,427 | $2,416 |
| 3 | $17,329 | $2,902 |
| 4 | $20,814 | $3,485 |
| 5 | $25,000 | $4,186 |
A growth rate is easy to measure and hard to sustain. If you are building the product largely on your own, Tekk turns what you want into specs your coding agent can actually execute.
The formula
CAGR = (ending value ÷ beginning value) ^ (1 ÷ years) − 1
That is the whole thing. The exponent is what makes it compound: dividing by the number of years would give you an average, and an average of percentage changes is not a growth rate.
Worked example
An investment worth $10,000 is worth $25,000 five years later.
(25,000 ÷ 10,000) ^ (1 ÷ 5) − 1 = 0.2011 → 20.11% a year
The path that rate produces:
| Year | Value | Gain that year |
|---|---|---|
| Start | $10,000 | — |
| 1 | $12,011 | $2,011 |
| 2 | $14,427 | $2,416 |
| 3 | $17,329 | $2,902 |
| 4 | $20,814 | $3,485 |
| 5 | $25,000 | $4,186 |
Total growth is 150%. The annual rate is 20.11%. Straight-line growth would add $3,000 every year, so it runs ahead of the compounded path early and gets overtaken near the end — that crossing is the whole difference between an average and a compound rate.
Solving in the other three directions
Start, end, years and rate are four numbers that fix each other. Any three give the fourth:
| To find | Formula |
|---|---|
| Rate | (end ÷ start) ^ (1 ÷ years) − 1 |
| Ending value | start × (1 + rate) ^ years |
| Starting value | end ÷ (1 + rate) ^ years |
| Years | ln(end ÷ start) ÷ ln(1 + rate) |
The last one answers the question people actually have: at 20% a year, doubling takes 3.8 years.
Where it misleads
CAGR reads the endpoints and nothing else, so a violent path and a smooth one that finish in the same place return the same number. The standard demonstration: $1,000 rises 25% to $1,250, then falls 25% to $937.50. The average of +25% and −25% is zero, but the CAGR is about −3.2% a year — and neither figure tells you the value swung by a quarter twice.
Two consequences worth remembering. Pick the endpoints and you pick the answer, which is why growth charts in fundraising decks so often begin at a trough. And if money moved in or out during the period, CAGR is the wrong tool — that is what IRR is for.
How it works
- 1
Choose what you're solving for
Most people want the rate, so that is the default. Switch it to the ending value to project forward, to the starting value to work back from a target, or to the number of years to find out how long a rate takes to get there.
- 2
Fill in the other three
The three remaining fields are your knowns. Everything recalculates as you type — no submit button, nothing sent to a server, and the CAGR calculator returns an em dash rather than a nonsense figure when a combination has no answer.
- 3
Read the curve against the straight line
The chart plots the compounded path next to straight-line growth between the same two points. The gap between them is why an annualised rate is lower than the total growth divided by the number of years, and the table below breaks the same path down year by year.
Frequently asked questions
- What is CAGR?
- Compound annual growth rate: the single steady rate that would take a starting value to an ending value over a given period. It is a smoothing device. Real growth is lumpy, and CAGR replaces that lumpiness with the one constant rate that lands on the same endpoint, which is what makes two investments over different time spans comparable at all.
- How do you calculate CAGR?
- Divide the ending value by the starting value, raise the result to the power of one divided by the number of years, then subtract one. For $10,000 growing to $25,000 over five years that is (25000 ÷ 10000) ^ (1 ÷ 5) − 1, which is 20.11% a year.
- What is the CAGR calculator Excel formula?
- In a spreadsheet it is =(B2/A2)^(1/C2)-1 with the ending value in B2, the starting value in A2 and the years in C2, formatted as a percentage. Excel also has RRI, so =RRI(C2,A2,B2) gives the same answer. Anyone reaching for a CAGR calculator Excel formula usually wants a second opinion on the result, which is the fastest use of this page.
- What does this CAGR growth rate calculator do that a spreadsheet doesn't?
- It solves in four directions rather than one. A spreadsheet formula gives you the rate; getting the ending value or the number of years back out means writing two more formulas. A CAGR growth rate calculator that works in every direction also draws the compounded path, which is the part that changes how people read the number.
- What is the difference between CAGR and average annual growth rate?
- Average annual growth rate takes each year's percentage change and averages them. CAGR compounds instead. Growing 50% then falling 50% averages to zero, but the compound result is a 13.4% annual loss — you end at 75% of where you started. The average is the more flattering number and almost always the wrong one.
- Why does this CAGR calculator show total growth as well as the annual rate?
- Because they get confused constantly. Total growth is how much the value changed across the whole period; CAGR is the annualised rate that produces it. $10,000 to $25,000 is 150% total growth and 20.11% a year. Quoting the first as if it were the second is one of the most common mistakes in a pitch deck.
- Can CAGR be negative?
- Yes. Any ending value below the starting value gives a negative rate, and the tool handles it the same way as growth. It has one hard limit: an ending value of exactly zero has no finite rate, because no percentage repeated over several years reaches zero. That case returns an em dash instead of a number.
- What is a good CAGR?
- It only means something against a benchmark. Broad equity indices have historically compounded in the high single digits over long periods; venture investors typically look for far more from an early-stage company; a mature business growing at inflation is holding position rather than growing. Compare like with like, over the same span.
- Does CAGR hide volatility?
- Yes, and that is the main criticism of it. An investment that rose 25% then fell 25% ends at 93.75% of where it started, a CAGR of about −3.2% a year — a number that gives no hint the ride was that rough. CAGR describes the endpoints and says nothing about the path between them.
- How many years should I use?
- The actual elapsed time between the two values, decimals included. Counting calendar years instead of elapsed years is the usual error: 2020 to 2024 is four years of growth, not five. Decimals are fine here, so 18 months is 1.5.
- What is the difference between CAGR and IRR?
- CAGR looks at two points and ignores everything in between, so it assumes a single sum left alone. IRR handles cash flows moving in and out along the way. If money was added or withdrawn during the period, CAGR will overstate or understate the return and IRR is the right measure.
- Do you store the numbers I enter?
- No. The calculation runs entirely in your browser. Nothing is sent to a server, nothing is logged, and there is no account. Disconnect from the internet and it will still work.
- Why is this free, and what is Tekk?
- Tekk is a spec-driven development platform for people building software with AI coding agents. This calculator costs us nothing to run, and the founders working out a growth rate are often the same people building the product. No signup, no run limit, no upsell inside the tool.
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