XIRR vs CAGR: Which Return Measure Should You Use?

Two investors can describe the same investment with two very different return numbers and both be right. CAGR measures how a single lump sum grew over a period. XIRR measures the annualised return on a series of cash flows that happen on different dates. Confusing the two is one of the most common reasons people misjudge a SIP, a portfolio or a business investment.

This guide explains both measures in plain language, works through the same example using each method, and gives you a simple rule for when to use which.

Two measures, two different questions

CAGR answers: if I invested one amount at the start, what constant annual rate would turn it into the ending value? XIRR answers: given every deposit and withdrawal on its actual date, what constant annual rate makes the present value of all cash flows equal to zero?

CAGR is a time-weighted growth measure for a single starting amount. XIRR is a money-weighted measure for an irregular stream of cash flows. The difference matters most when you add money gradually, as you do with a SIP.

What CAGR tells you

The CAGR formula is ending value ÷ beginning value, raised to the power of 1 ÷ number of years, minus 1. If ₹5 lakh grows to ₹7 lakh in five years, the CAGR is (7,00,000 ÷ 5,00,000)^(1/5) − 1, which is about 6.96%.

CAGR is useful because it smooths a volatile path into one comparable number. A fund that returned 40% in year one and lost 10% in year two has a CAGR that reflects the compounded result, not the arithmetic average.

Where CAGR breaks down

CAGR assumes the entire beginning value was invested for the whole period. That is true for a lump sum, but not for a SIP. If you invest ₹1 lakh every year for five years, the first instalment is invested for five years, the second for four, and the last for only one. Treating the ₹5 lakh total as if it were invested at the start overstates how long the money worked.

CAGR also struggles with withdrawals, top-ups, dividends and reinvestment. You can calculate a CAGR on the ending value, but it will not tell you the return earned on the actual capital deployed.

What XIRR does differently

XIRR uses dated cash flows. Money you invest is negative, money you receive is positive. The calculation finds the annual rate at which the net present value of all those flows is zero. Spreadsheets and financial calculators solve it iteratively because there is no simple closed-form formula.

The total invested is ₹5 lakh and the ending value is ₹7 lakh, a profit of ₹2 lakh. The XIRR is about 11.43%. That is much higher than the 6.96% CAGR on the same total because most of the money was invested for less than five years.

Why the gap is so large

CAGR gives every rupee the full five years of compounding. XIRR gives each instalment only the time it was actually invested. The later instalments had less time to grow, so the ending profit represents a higher annual rate on the capital that was deployed early.

None of these numbers is wrong. They answer different questions. If you want to compare your SIP with a fixed deposit, XIRR is the fair comparison because the FD also receives money at different times. If you want to compare two funds over the same five-year period with a lump sum, CAGR is simpler.

When to use CAGR

• A single lump-sum investment held for a known period.
• Comparing two funds, indices or asset classes over the same start and end dates.
• Projecting a goal where you invest once and let it compound.
• Measuring business revenue or profit growth over several years.
• Reporting a simple annualised return in a presentation.

When to use XIRR

• A SIP with monthly or quarterly contributions.
• A portfolio with purchases, sales, dividends and withdrawals.
• An SWP where you withdraw regularly.
• A real estate investment with rental income and a final sale.
• A private business or startup investment with multiple funding rounds.
• Any comparison where the timing of cash flows differs between options.

How to calculate both

1. List every cash flow with its exact date; outflows are negative and inflows are positive.
2. For CAGR, use the beginning value, ending value and the number of years.
3. For XIRR, use the XIRR function in Excel or Google Sheets with the values and dates.
4. Check that the final value includes all withdrawals and the ending balance.
5. Use the XIRR calculator or CAGR calculator if you prefer not to build a spreadsheet.

Common mistakes

• Comparing a SIP's XIRR with a lump sum's CAGR and concluding one is better.
• Using the total invested amount as the beginning value for a SIP CAGR.
• Ignoring the dates of deposits and withdrawals.
• Using XIRR for a holding period of a few weeks, where the annualised number is unstable.
• Forgetting to include the ending balance or a final withdrawal.
• Mixing pre-tax and post-tax cash flows in the same comparison.
• Entering all cash flows with the same sign, which makes the calculation fail.

What about taxes and fees?

Both measures can be calculated on a pre-tax or post-tax basis. For a true picture, reduce each withdrawal by exit load and tax, and include any reinvested dividends. Expense ratios are already reflected in the NAV, so you do not need to subtract them again. If you are comparing a mutual fund with an FD, use post-tax cash flows for both.

A simple decision table

Bottom line

CAGR is a clean way to describe compounded growth for a single starting amount. XIRR is the honest measure when money goes in and out at different times. If you invest through a SIP, learn to read XIRR; if you compare funds, learn to read CAGR. Understanding both keeps you from being impressed by the wrong number.