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IRR Calculator: Internal Rate of Return Made Simple

Calculator200 Editorial Team — published September 2026

An IRR calculator answers the question every investor eventually faces: is this project worth my capital? The internal rate of return is the annual percentage yield at which an investment breaks even — where the present value of every rupee or dollar flowing in equals the present value of everything flowing out. Enter your cash flows into a free IRR calculator, and it returns the rate that makes net present value zero. That single number lets you compare a rental property against a mutual fund SIP, a new factory against an expansion, or a private equity deal against a bond — all on the same scale.

What the Internal Rate of Return Actually Measures

Strip away the financial jargon and IRR is a break-even interest rate. Imagine you borrow money to fund a project. If the project generates returns at exactly the rate you borrowed at, your net gain is zero. IRR tells you that rate.

Formally, IRR is the discount rate r that satisfies this equation:

NPV = CF₀ + CF₁/(1+r)¹ + CF₂/(1+r)² + ... + CFₙ/(1+r)ⁿ = 0

Where CF₀ is the initial investment (a negative number), and CF₁ through CFₙ are the expected cash flows in each subsequent period. The equation cannot be solved algebraically for r when there are more than two cash flows. Calculators and spreadsheets use iterative numerical methods — trial and error refined by algorithm — to converge on the answer.

That iterative nature is why a proper calculator matters. Manual IRR calculation with the interpolation method is possible but slow, and small arithmetic slips compound quickly. The IRR calculator on this site handles the iteration instantly.

IRR vs NPV: Two Sides of the Same Coin

NPV and IRR come from the same discounted cash flow framework, but they answer different questions. NPV asks: how much value does this project create in absolute terms? IRR asks: what percentage return does this project generate on the capital employed?

A positive NPV at your required rate of return means the project adds value. An IRR above that required rate means the same thing. The two metrics always agree on whether a single project is acceptable. They can disagree on which project to choose when comparing mutually exclusive options.

BasisNPVIRR
OutputCurrency amountPercentage rate
Decision ruleAccept if NPV > 0Accept if IRR > hurdle rate
Project rankingReliable for mutually exclusive projectsCan mislead when project scales differ
Reinvestment assumptionCash flows reinvested at the discount rateCash flows reinvested at the IRR itself
Multiple solutionsNeverPossible with unconventional cash flows

The reinvestment difference is the most consequential. A project with a 40% IRR implicitly assumes you can redeploy every interim cash flow at 40%. In practice, you will park that money in a bank fixed deposit at 6–8% or a liquid fund at 7%. This is not a minor technicality — it can distort project rankings significantly.

Calculating IRR in Excel and Google Sheets

Spreadsheets offer three functions, each suited to a different cash flow pattern.

IRR Function — For Regular Intervals

The standard IRR function assumes cash flows occur at equal intervals — every year or every month. The syntax is simple:

=IRR(B2:B7)

Enter the initial investment as a negative number in the first cell, followed by positive cash inflows. If your data starts with an outflow of ₹100,000 in year zero and returns ₹25,000, ₹30,000, ₹35,000, ₹30,000, and ₹20,000 over five years, the formula returns the annual rate at which those flows break even.

XIRR Function — For Irregular Dates

This is the function that matters for real-world investing. Mutual fund SIPs debit your account on the 5th of every month. Rental income arrives on varying dates. A business receives payments according to customer cycles, not calendar quarters. XIRR accepts a date column alongside the cash flow column:

=XIRR(B2:B20, A2:A20)

Each cash flow is paired with its actual date. The function calculates the annualised return that accounts for the exact timing of every inflow and outflow. In India, most mutual fund platforms and Consolidated Account Statements report SIP returns using XIRR for precisely this reason — a 10% XIRR on a SIP is not the same as a 10% CAGR on a lump sum.

Google Sheets supports all three functions — IRR, XIRR, and MIRR — with identical syntax. If you are tracking a portfolio, structure your data as two columns: one for dates, one for cash flows. Keep the initial investment as a negative value and every return as positive.

MIRR Function — For a Realistic Reinvestment Assumption

The modified internal rate of return separates the rate at which you borrow from the rate at which you reinvest. This eliminates the unrealistic reinvestment assumption embedded in standard IRR.

=MIRR(B2:B7, finance_rate, reinvest_rate)

The finance_rate is the interest you pay on the capital used for the initial investment — your weighted average cost of capital, or WACC. The reinvest_rate is what you realistically earn on interim cash flows, such as a fixed deposit rate. MIRR is always lower than IRR when the reinvestment rate is lower than the IRR, and it gives a more conservative, defensible number for board presentations and investment committee memos.

Step-by-Step Manual IRR Calculation

Understanding the manual method helps you sanity-check calculator outputs. The interpolation approach works like this:

  1. Set up the cash flows. List the initial outflow (negative) and each subsequent inflow (positive) in chronological order.
  2. Pick two discount rates. Choose one that produces a positive NPV and one that produces a negative NPV. The IRR lies between them.
  3. Calculate NPV at each rate. Use the NPV formula with each of your two chosen rates.
  4. Interpolate. Apply this formula: IRR = Lower Rate + (NPV at Lower Rate / (NPV at Lower Rate − NPV at Higher Rate)) × (Higher Rate − Lower Rate).

Take a project with an initial investment of ₹100,000 and cash inflows of ₹30,000, ₹35,000, ₹40,000, and ₹30,000 over four years. At a 10% discount rate, NPV is positive. At 15%, NPV turns negative. Interpolation gives an IRR of roughly 12.4%. A calculator returns 12.38% — close enough for decision-making, but the calculator is faster and free of rounding errors.

IRR vs CAGR: When Each Metric Fits

CAGR and IRR both express returns as an annual percentage, but they serve different purposes. CAGR measures the smooth growth rate of a single lump-sum investment from start to finish. It ignores everything that happens in between. IRR incorporates the timing and size of every cash flow.

ScenarioUse CAGRUse IRR / XIRR
One-time investment, redeemed after five yearsYesWorks, but CAGR is simpler
Monthly SIP into a mutual fundNoYes — XIRR is the correct function
Real estate with rental income and a final saleNoYes — rental timing matters
Business project with phased capital expenditureNoYes — interim outflows affect return
Comparing fund performance over a fixed periodYes — standard industry practiceUseful if you invested lump sums at different times

If you made a single investment of ₹1,00,000 and it grew to ₹2,00,000 in seven years, CAGR tells you the annual growth rate: approximately 10.4%. If you invested ₹10,000 every month for seven years and the portfolio is now worth ₹12,00,000, XIRR tells you the return on your actual capital deployed — and that number will differ from what a simple point-to-point return calculation would suggest.

Real-World Applications Across Markets

Real Estate

Property investors use IRR to account for rental income, capital expenditure, and the eventual sale proceeds. Two properties may both sell for twice the purchase price, but if one generates rental income from year one and the other sits vacant for two years, their IRRs will diverge sharply. A leveraged property — where a mortgage amplifies both gains and losses — produces an equity IRR that is higher than the unlevered property IRR in a rising market, and lower in a falling one.

Mutual Funds and SIPs

XIRR is the standard metric for evaluating SIP performance in India. A 2026 analysis of equity funds found that several midcap and smallcap schemes delivered SIP XIRRs above 19% over five-year periods, while large-cap funds typically ranged between 12% and 16%. These figures vary with entry timing and fund selection, but they illustrate why XIRR — not CAGR — is the number to check on your CAS statement.

Private Equity and Venture Capital

PE and VC funds report gross IRR and net IRR. Gross IRR measures portfolio performance before fees and carried interest. Net IRR is what limited partners actually receive after the general partner takes management fees and a share of profits. The gap between the two — often 300 to 500 basis points in venture funds — is why sophisticated investors focus on net IRR when evaluating fund managers.

Corporate Capital Budgeting

Companies use IRR alongside NPV when deciding between competing projects. A manufacturing firm choosing between upgrading an existing production line and building a new facility will calculate the IRR of each. If capital is limited, the project with the higher IRR per unit of capital deployed may be preferred — though NPV remains the theoretically superior ranking tool because it measures absolute value creation.

Limitations That Matter in Practice

IRR is not a perfect metric. Knowing its weaknesses prevents costly misjudgements.

Multiple IRRs

When a project's cash flows change sign more than once — an initial outflow, a large inflow, then another outflow for refurbishment — the IRR equation can have more than one solution. A conventional project has one outflow followed by inflows, producing a single IRR. An unconventional pattern can produce two or more mathematically valid IRRs. MIRR avoids this entirely.

The Reinvestment Assumption

Standard IRR assumes every interim cash flow is reinvested at the IRR itself. If the IRR is 25%, the model assumes you can find 25% returns for every rupee returned during the project's life. That assumption rarely holds. MIRR corrects it by letting you specify a realistic reinvestment rate.

Scale Bias

IRR is expressed as a percentage, not an absolute amount. A small project with a 40% IRR may create less total value than a large project with a 15% IRR. When capital is abundant, NPV is the safer selection criterion. When capital is constrained, IRR helps allocate limited funds to the most efficient uses.

IRR Benchmarks by Region and Asset Class

What counts as a good IRR depends on where you invest and what you invest in. The following benchmarks reflect typical market conditions and are not guarantees.

MarketAsset ClassTypical IRR RangeReference Point
IndiaReal estate (residential)8–12%Fixed deposit rates of 6–8%
IndiaEquity mutual fund SIP10–16%Nifty 50 long-term returns
United StatesCore real estate6–9%10-year Treasury yield
United StatesValue-add real estate12–18%Leverage amplifies returns
United KingdomInfrastructure projects7–10%Gilt yields plus risk premium
GlobalPrivate equity buyout15–20% (gross)Net IRR typically 3–5% lower
GlobalVenture capital20–30% (gross, top quartile)Net IRR after fees and carry
These ranges are indicative. Actual returns depend on entry timing, leverage, operational performance, and exit conditions. Past performance does not guarantee future results.

Common Mistakes When Using an IRR Calculator

Three errors account for most IRR miscalculations.

Sign convention. The initial investment must be entered as a negative number. Some users enter it as positive and get an IRR that makes no sense. Every outflow is negative; every inflow is positive. The IRR equation requires at least one negative and one positive value.

Mixing annual and monthly periods. The IRR function returns a rate per period. If your cash flows are monthly, the result is a monthly IRR. Annualising it requires compounding, not simple multiplication. Multiply a monthly IRR by 12 and you overstate the annual return. The correct conversion is (1 + monthly IRR)¹² − 1.

Ignoring the date column. If cash flows arrive on irregular dates, the standard IRR function gives a wrong answer. Use XIRR with a date column. This is not optional — it is the difference between a defensible number and a misleading one.

Frequently Asked Questions

What is the difference between IRR and XIRR?

IRR assumes cash flows occur at regular intervals — every year or every month. XIRR accepts specific dates for each cash flow, which makes it the correct function for SIPs, mutual fund redemptions, or any investment where money moves in and out on irregular dates.

How do I calculate IRR in Excel?

Use =IRR(range) for regular annual cash flows and =XIRR(values, dates) for cash flows with specific dates. Enter the initial investment as a negative number. The function returns the annual rate at which the net present value equals zero.

What is a good IRR?

It depends on the asset and risk. Real estate investors often target 8–12% for core assets and 15–20% for value-add plays. Business projects should clear the company's cost of capital, usually 8–15%. In India, comparing IRR against fixed deposit rates of 6–8% gives a simple reality check.

Why does IRR sometimes give two answers?

When a project's cash flow pattern switches signs more than once — for example, an initial outflow, a large inflow, then another outflow for refurbishment — the IRR equation can have multiple solutions. MIRR avoids this by separating the finance rate from the reinvestment rate.

Is IRR better than NPV?

Neither is universally better. NPV tells you the absolute value created in currency terms, which is what wealth maximisation is about. IRR tells you the efficiency of capital — the percentage return. For mutually exclusive projects with different scales, NPV is the safer decision rule.

How is XIRR used for mutual fund SIP returns?

Each SIP instalment has a different holding period. XIRR treats every instalment as a separate cash flow with its own date, so it calculates the true annualised return on your actual invested capital. Most Indian mutual fund platforms and CAS statements report SIP returns using XIRR.

Can IRR be negative?

Yes. A negative IRR means the investment destroys value — the discounted cash inflows are worth less than the initial outflow. This happens when total returns fall short of the capital invested after accounting for the timing of cash flows.

What reinvestment rate does IRR assume?

IRR implicitly assumes that every interim cash flow is reinvested at the IRR itself. If the IRR is 25%, the model assumes you can find other investments yielding 25% for every rupee or dollar returned during the project. That assumption is often unrealistic, which is why MIRR exists.

An IRR calculator converts a messy stream of dated cash flows into a single, comparable percentage — the rate at which your investment breaks even. It is the most practical tool for comparing opportunities of different sizes, durations, and cash flow patterns, provided you understand what it measures and where it can mislead. Use XIRR when dates are irregular, MIRR when the reinvestment assumption matters, and always sanity-check the output against NPV before making a capital commitment. The internal rate of return calculator on this site gives you the number; the judgement about whether that number is good enough remains yours.