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Finance & Accounting

Internal Rate of Return (IRR) Calculator

Find the discount rate that makes a project NPV equal to zero, used for capital budgeting and investment comparison.

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The upfront capital invested at the start of the project.

Enter projected cash inflows for each year. Negative values represent additional outflows.

Your Results

%

Enter cash flows and click calculate.

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Introduction

When a private equity firm presents a 28% IRR on a fund, that number is the rate that makes the present value of all distributions exactly equal to the capital invested. It is the most widely cited performance metric in investment management, used by venture capital, real estate, infrastructure, and buyout funds globally. The CFA Institute includes IRR as a core capital budgeting metric, but also flags its limitations: it assumes cash flows are reinvested at the IRR itself, which for very high returns, is often unrealistic. This calculator computes IRR precisely using the Newton-Raphson iterative method and shows you the implied annual return on your investment, so you can compare opportunities on an equal basis regardless of their size or duration.

What This Calculator Does

This Internal Rate of Return calculator finds the discount rate at which the Net Present Value of a series of cash flows equals exactly zero. Enter an initial investment (as a negative cash flow at Year 0) and the projected annual cash inflows for each subsequent year. The calculator solves for the IRR using iterative numerical methods and returns the annualized percentage return. It also displays the NPV at your specified hurdle rate for comparison.

The Formula

0 = -Initial Investment + Sum of [Cash Flow(t) / (1 + IRR)^t] for t = 1 to n

IRR is the rate r that makes this equation true: the sum of all discounted cash flows, including the initial negative investment at Year 0, equals zero. Unlike NPV where you specify the rate, IRR solves for it. Because the equation is polynomial, it cannot be solved algebraically for most cash flow patterns. The Newton-Raphson method iterates from an initial estimate, refining until the result converges within a tolerance of 0.0001%.

Step-by-Step Example

1

Enter the initial investment

The upfront capital outlay as a positive number (the calculator treats it as a negative cash flow at Year 0). Example: $200,000.

2

Enter annual cash inflows

Projected net cash returns for each year. Example: Year 1: $35,000. Year 2: $50,000. Year 3: $65,000. Year 4: $75,000. Year 5: $90,000 (including salvage).

3

Review the IRR

IRR calculates to approximately 19.1%. Compare against your hurdle rate (minimum acceptable return). If your WACC or required return is 12%, this project clears the threshold with margin.

4

Compare with NPV at hurdle rate

At 12% discount rate, NPV = $44,800 (positive, confirming IRR exceeds hurdle). At 20% discount rate, NPV = -$4,300 (negative, confirming IRR is below 20%). These two data points bracket the exact IRR.

Real-World Use Cases

Real Estate Investment Comparison

An investor comparing two properties projects 5-year hold periods with different purchase prices, rent income, and exit values. Property A shows a 14.2% IRR; Property B shows an 11.8% IRR. Both clear the 9% hurdle rate, but Property A is preferred on return basis. The investor confirms Property A also has the higher NPV before deciding.

Venture Capital Fund Performance

A fund manager calculates IRR across the fund's portfolio to report to limited partners. Each investment's entry date, exit proceeds, and interim distributions feed into an IRR calculation. The fund-level IRR weights the timing and magnitude of every cash movement since inception.

Equipment vs. Lease Decision

A logistics company comparing a $600,000 equipment purchase (saving $140,000/year in lease costs over 6 years with $80,000 salvage) against continuing to lease calculates the purchase IRR at 17.3%. Since this exceeds their 10% cost of capital, buying is financially superior.

Comparison

InvestmentCash Flows (Years 1-5)IRRNPV at 10%Decision vs 10% Hurdle
$100,000$20K/$25K/$30K/$35K/$40K16.8%$18,950Accept
$100,000$15K/$20K/$25K/$30K/$50K14.9%$11,270Accept
$100,000$10K/$15K/$20K/$25K/$30K8.2%-$9,170Reject
$100,000$35K/$35K/$35K/$35K/$35K22.1%$32,750Accept
$100,000$5K/$10K/$20K/$40K/$80K18.4%$21,430Accept

Common Mistakes to Avoid

  • Using IRR to compare projects of different sizes. A 40% IRR on a $10,000 investment creates $4,000 in Year 1 value. A 20% IRR on a $500,000 investment creates $100,000. IRR alone does not reveal which project creates more wealth. Always check absolute NPV.

  • Accepting IRR without checking for multiple solutions. When cash flows change sign more than once (a large outflow in Year 3, for example), the IRR equation can have multiple mathematical solutions. In these cases, the Modified IRR (MIRR) or NPV profile is more reliable.

  • Treating a high IRR as automatically achievable. IRR assumes all interim cash flows are reinvested at the IRR rate. A 35% IRR project implicitly assumes you can reinvest distributions at 35% indefinitely. MIRR corrects this by using a realistic reinvestment rate, typically WACC.

  • Ignoring the time horizon difference when comparing two IRRs. A project returning 20% IRR over 2 years creates less absolute value than a 20% IRR project over 8 years, assuming available capital. Longer positive-IRR periods compound more total wealth.

Frequently Asked Questions

Accuracy and Disclaimer

IRR is calculated using the Newton-Raphson iterative method assuming reinvestment of cash flows at the IRR rate. For projects with non-conventional cash flows (multiple sign changes), multiple IRR solutions may exist. In those cases, use MIRR or NPV analysis. This calculator is for educational and planning purposes. Consult a financial analyst or investment professional for formal investment decisions.

Conclusion

IRR is most powerful when used alongside NPV, not instead of it. IRR tells you the percentage return; NPV tells you the dollar value created. A 35% IRR on a $50,000 investment creates less absolute wealth than a 20% IRR on a $1,000,000 investment. Use this calculator to screen projects quickly, then validate the winners with the NPV Calculator to confirm dollar value creation. For real estate investments specifically, pair IRR with cash-on-cash return and the Cap Rate Calculator for a complete investment picture.