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Internal Rate of Return (IRR) Calculator

Calculate the internal rate of return — the discount rate that makes net present value zero. Compare against your cost of capital to evaluate investments.

Reviewed by Christopher FloiedUpdated

This free online internal rate of return (irr) calculator provides instant results with no signup required. All calculations run directly in your browser — your data is never sent to a server. Enter your values below and see results update in real time as you type. Perfect for everyday calculations, homework, or professional use.

How to Use This Calculator

1

Enter your input values

Fill in all required input fields for the Internal Rate of Return (IRR) Calculator. Most fields include unit selectors so you can work in your preferred unit system — metric or imperial, whichever matches your problem.

2

Review your inputs

Double-check that all values are correct and that you have selected the right units for each field. Incorrect units are the most common source of calculation errors and can produce results that are off by factors of 2, 10, or more.

3

Read the results

The Internal Rate of Return (IRR) Calculator instantly computes the output and displays results with units clearly labeled. All calculations happen in your browser — no loading time and no data sent to a server.

4

Explore parameter sensitivity

Try adjusting individual input values to see how the output changes. This is a quick and effective way to develop intuition about how different parameters influence the result and to identify which inputs have the largest effect.

Formula Reference

Internal Rate of Return (IRR) Calculator Formula

See calculator inputs for the governing equation

Variables: All variables and their units are labeled in the calculator interface above. Input fields accept values in multiple unit systems — select your preferred unit from the dropdown next to each field.

When to Use This Calculator

  • •Use the Internal Rate of Return (IRR) Calculator when comparing financial options side-by-side — such as different loan terms or investment returns — to make more informed decisions.
  • •Use it to quickly estimate costs or returns before making purchasing, investment, or borrowing decisions.
  • •Use it for financial education and planning to understand how compound interest, fees, or tax affects the real value of money over time.
  • •Use it when building or reviewing a budget to verify that projections and calculations are mathematically correct.

About This Calculator

The Internal Rate of Return (IRR) Calculator is a free financial calculation tool designed to help individuals and businesses understand key financial concepts and estimate costs, returns, and loan parameters. Calculate the internal rate of return — the discount rate that makes net present value zero. Compare against your cost of capital to evaluate investments. The calculations are based on standard financial mathematics formulas. Results are for informational and educational purposes only and should not be considered financial, investment, or tax advice. Consult a qualified financial professional before making financial decisions. All calculations are performed in your browser — no personal financial data is stored or transmitted.

About Internal Rate of Return (IRR) Calculator

The Internal Rate of Return (IRR) Calculator shows the annualized return of an investment — the percentage rate that makes the present value of all cash flows equal to the initial cost. IRR is one of the most widely-used metrics in finance because it converts complex investment scenarios into a single, intuitive percentage that can be compared against your cost of capital or alternative investments. Private equity firms, real estate investors, venture capitalists, and corporate finance teams all rely on IRR to evaluate opportunities. An IRR of 15% means the investment effectively earns 15% per year when all cash flows are properly accounted for — directly comparable to other investment options.

The Math Behind It

The Internal Rate of Return (IRR) is the discount rate that makes the net present value of all cash flows from an investment equal to zero. It represents the annualized effective return. **The Formula**: 0 = Σ CF_t / (1+IRR)^t - C_0 Solving for IRR typically requires iteration or financial calculator — there's no closed-form solution for multi-period cash flows. **Simple Case (Lump Sum)**: When you have one investment and one lump-sum return: IRR = (FV/PV)^(1/n) - 1 Example: $10,000 becomes $15,000 in 5 years IRR = (15000/10000)^(1/5) - 1 = 1.5^0.2 - 1 = 1.0845 - 1 = 8.45% **Decision Rule**: - **IRR > cost of capital**: Accept (creates value) - **IRR < cost of capital**: Reject (destroys value) - **IRR = cost of capital**: Indifferent **Interpreting IRR**: | IRR | Interpretation | |-----|----------------| | 5% | Below most costs of capital — poor | | 8-10% | Market-rate return — average | | 12-15% | Good, beats most alternatives | | 20%+ | Excellent, typical VC target | | 30%+ | Exceptional, LBO/PE target | **IRR vs NPV**: - **NPV**: Dollar value added (absolute wealth) - **IRR**: Percentage return (relative) Both should give same accept/reject decisions for conventional projects, but they can rank projects differently. **When IRR Misleads**: 1. **Multiple IRRs**: Non-conventional cash flows (sign changes) can have multiple valid IRRs 2. **Scale problems**: Small project with high IRR may be worse than large project with lower IRR but higher NPV 3. **Reinvestment assumption**: IRR assumes cash flows are reinvested at the IRR itself — often unrealistic 4. **Timing differences**: Projects with different time horizons can't always be compared via IRR alone **MIRR (Modified IRR)**: Addresses reinvestment issue by assuming cash flows are reinvested at the firm's cost of capital: MIRR = (FV of positive flows / PV of negative flows)^(1/n) - 1 More realistic but less common. **Real Estate IRR**: In real estate, IRR includes: - Purchase price (initial outflow) - Annual rental income minus expenses - Property appreciation (captured at sale) - Sale price minus selling costs **VC/PE IRR Expectations**: - **Venture Capital**: 25-30%+ target (most investments fail) - **Private Equity/LBO**: 20-25% target - **Real Estate**: 15-20% value-add; 8-12% stabilized - **Hedge Funds**: 10-15% target - **Traditional stocks**: 7-10% long-run average

Formula Reference

Simple IRR (lump sum)

IRR = (FV/PV)^(1/n) - 1

Variables: FV = final value, PV = initial investment, n = years

General IRR

0 = Σ CF_t / (1+IRR)^t

Variables: Solved numerically for irregular cash flows

Worked Examples

Example 1: Simple Investment

$50,000 invested becomes $90,000 in 7 years.

Step 1:IRR = (90000/50000)^(1/7) - 1
Step 2:IRR = 1.8^(0.1429) - 1
Step 3:IRR = 1.0881 - 1
Step 4:IRR = 0.0881 = 8.81%

The investment earned 8.81% annualized — above the stock market average of ~10% real, but below nominal S&P 500 averages. Acceptable if your cost of capital is below 8.81%.

Example 2: Real Estate Flip

Buy property for $200,000, renovate for $50,000, sell for $350,000 after 1 year.

Step 1:Total investment: $200,000 + $50,000 = $250,000
Step 2:Net return: $350,000 - $250,000 = $100,000
Step 3:IRR = (350000/250000)^(1/1) - 1
Step 4:IRR = 1.4 - 1 = 40%

IRR = 40% in one year. Excellent return, but must consider: time intensity, selling costs, taxes, and that one year is short — not reliable long-term. Factor in carrying costs and selling fees for a more accurate figure.

Common Mistakes & Tips

  • !Comparing IRR to CAGR without understanding the difference. IRR handles intermediate cash flows; CAGR is only for lump sums.
  • !Preferring higher IRR on a small project over lower IRR on a large project. Absolute dollar NPV matters too.
  • !Ignoring the reinvestment assumption. If you can't actually reinvest at IRR, your real return is lower.
  • !Using simplified IRR (just FV/PV growth rate) when there are actually multiple cash flows per period.

Related Concepts

NPV

Net Present Value — pairs with IRR for decisions.

CAGR

Compound Annual Growth Rate for pure lump sum investments.

DCF Analysis

Full DCF model using IRR concepts.

Frequently Asked Questions

What's the difference between IRR and CAGR?

CAGR assumes a single initial investment and a single final value — no intermediate cash flows. IRR can handle any pattern of cash flows (multiple investments, regular distributions, reinvestments). For simple 'buy and hold' investments, IRR and CAGR give identical results. For investments with periodic cash flows (rental property, dividend stocks, bonds), use IRR.

What's a 'good' IRR?

Depends entirely on your alternatives and risk level. In general: below 5% is poor (worse than bonds), 8-10% matches market averages, 12-15% beats market, 20%+ is excellent for most investments. Venture capital targets 25-30%. Private equity targets 20%+. Real estate development targets 15-20%. The critical comparison is always against YOUR cost of capital.

Why does the IRR assume reinvestment at the IRR?

This is a mathematical consequence of the formula — not a realistic assumption. In reality, you're unlikely to find another investment earning 30% to reinvest your returns. This is why IRR can overstate actual returns, especially for high-IRR short-duration projects. Modified IRR (MIRR) addresses this by assuming reinvestment at the cost of capital.

Can IRR be negative?

Yes. Negative IRR means the investment lost money over time. For example, investing $100,000 and having $80,000 after 5 years gives IRR ≈ -4.4%. Negative IRR automatically means the investment should have been rejected. Note: if the undiscounted total return is negative (final < initial), IRR is definitively negative.