The compound annual growth rate, or CAGR for short, measures the return on an investment over a certain period of time. The internal rate of return, or IRR, also measures investment performance but is more flexible than CAGR.
CAGR
The concept of CAGR is relatively straightforward and requires only three primary inputs: an investment’s beginning value, ending value, and the time period. Online tools, including Investopedia’s CAGR calculator, will spit out the CAGR when entering these three values. The CAGR is superior to average returns because it considers the assumption that an investment is compounded over time. One limitation is that it assumes a smoothed return over the time period measured, only taking into account an initial and a final value when, in reality, an investment usually experiences shortterm ups and downs. CAGR is also subject to manipulation as the variable for the time period is input by the person calculating it and is not part of the calculation itself. Consider the following investment:
Initial Value = 1,000
Final Value = 2,200
Time period (n) = 4
[(Initial Value) / (Final Value)] ^ (1/n)  1
In the above case, the CAGR is 21.7%
IRR
IRR is also a rate of return but is more flexible in that it considers multiple cash flows and periods. While CAGR simply uses the beginning and ending value, in reality cash inflows and outflows occur when it comes to investments. IRR can also be used in corporate finance when a project requires cash outflows upfront but then results in cash inflows as an investment pays off. Consider the following investment:
Time period 
Cash Flow 
0 
1000 
1 
400 
2 
500 
3 
600 
4 
700 
In the above case, using the Excel function “IRR,” we obtain 36.4%.
Differences Between CAGR and IRR
The most important distinction is that CAGR is straightforward enough that it can be calculated by hand. In contrast, more complicated investments and projects, or those that have many different cash inflows and outflows, are best evaluated using IRR. To back into the IRR rate, a financial calculator, Excel, or portfolio accounting system is ideal. The example above used Excel to calculate the IRR but computation on a financial calculator is similar.
The Bottom Line
The CAGR helps frame an investments return over a certain period of time. It has its benefits, but there are definite limitations that investors need to be aware of. With multiple cash flows, the IRR approach is usually considered to be better than CAGR.
RELATED FAQS

Why is the compound annual growth rate (CAGR) misleading when assessing longterm ...
The compound annual growth rate (CAGR) measures the return on an investment over a certain period of time. Below is an overview ... 
What's the difference between weighted average cost of capital (WACC) and internal ...
Both weighted average cost of capital (WACC) and internal rate of return (IRR) are great measures for assessing value, but ... 
Which is a better measure for capital budgeting, IRR or NPV?
In capital budgeting, there are a number of different approaches that can be used to evaluate any given project, and each ... 
What is the difference between the acid test ratio and working capital ratio?
Using liquidity ratios to determine the financial stability of a company is an important tool to accounting professionals ...

Compound Annual Growth Rate  CAGR
The yearoveryear growth rate of an investment over a specified ... 
Internal Rate Of Return  IRR
The discount rate often used in capital budgeting that makes ... 
Best's Capital Adequacy Relativity (BCAR)
A rating of an insurance company’s balance sheet strength. Best’s ... 
Deferred Tax Asset
A deferred tax asset is an asset on a company's balance sheet ... 
Earnings Per Share  EPS
The portion of a company's profit allocated to each outstanding ... 
Return On Investment  ROI
A performance measure used to evaluate the efficiency of an investment ...