Contents
- 1 IRR Calculator — Internal Rate of Return for Projects
- 1.1 Visual Breakdown
- 1.2 What is IRR?
- 1.3 IRR vs NPV vs XIRR — Quick Reference
- 1.4 Worked Example — Equipment Purchase Decision
- 1.5 Limitations of IRR — Watch Out
- 1.6 Hurdle Rates — Choosing the Right Benchmark
- 1.7 IRR in Real-Life Decisions
- 1.8 How IRR is Computed (Excel Formula)
- 1.9 Frequently Asked Questions
- 1.10 Explore More Tools
IRR Calculator — Internal Rate of Return for Projects
Calculate Internal Rate of Return for any investment or project. Compare with your hurdle rate, see NPV sensitivity, and make accept/reject decisions.
Visual Breakdown
What is IRR?
Internal Rate of Return (IRR) is the discount rate at which Net Present Value (NPV) of all cash flows from a project equals zero. It’s the implied annualised return a project will generate. Used to evaluate capital projects, M&A deals, and any investment with evenly-spaced cash flows. Higher IRR = better project (other things equal).
The IRR Decision Rule
| Result | Decision |
|---|---|
| IRR > Cost of Capital / Hurdle Rate | ACCEPT — Project creates value |
| IRR = Cost of Capital | INDIFFERENT — Break-even |
| IRR < Cost of Capital | REJECT — Better alternatives available |
IRR vs NPV vs XIRR — Quick Reference
| Metric | Output | Best For | Limitations |
|---|---|---|---|
| NPV | Rupees (₹) | Comparing competing projects with different sizes | Requires discount rate as input |
| IRR | Percentage (%) | Yardstick rate for evaluating standalone projects | Assumes reinvestment at IRR; multiple IRRs for non-conventional cash flows |
| XIRR | Percentage (%) | Real-world investments with irregular cash flow dates | Needs dates; more complex math |
| MIRR | Percentage (%) | Modified IRR; assumes reinvestment at cost of capital — more realistic | Requires reinvestment rate input |
| CAGR | Percentage (%) | Single buy-sell pairs | Doesn’t handle multiple cash flows |
| Payback Period | Years | Quick liquidity test | Ignores cash flows after payback & time value of money |
Worked Example — Equipment Purchase Decision
A manufacturer is evaluating a ₹10 lakh machine. Expected after-tax cash flows: Y1: ₹3L, Y2: ₹3.5L, Y3: ₹4L, Y4: ₹2.5L, Y5: ₹2L. Cost of capital: 10%.
| Initial Investment | (₹10,00,000) |
| Year 1 to 5 Total | ₹15,00,000 |
| Net Cash Flow | +₹5,00,000 |
| IRR (computed via iteration) | ~15.2% |
| NPV @ 10% Cost of Capital | +₹1,57,000 |
| Decision | ACCEPT (IRR 15.2% > Hurdle 10%; NPV positive) |
Limitations of IRR — Watch Out
- Reinvestment Assumption: IRR implicitly assumes intermediate cash flows are reinvested at IRR itself. For high-IRR projects (20%+), this is unrealistic. Use MIRR (Modified IRR) which assumes reinvestment at cost of capital.
- Multiple IRRs: If cash flow signs change multiple times (e.g., -100, +500, -200, +300), there can be multiple mathematical IRRs. Misleading. Use NPV instead.
- Scale Insensitive: A ₹1 lakh project with 30% IRR seems better than ₹10 crore project with 15% IRR. But absolute wealth creation favors the bigger one. Use NPV for ranking.
- Mutually Exclusive Projects: Don’t rely on IRR alone to choose between competing projects of different sizes/timing. NPV is the tiebreaker.
- Unconventional Cash Flows: Mining projects, decommissioning costs at end → late negative flows confuse IRR. Use NPV or MIRR.
Hurdle Rates — Choosing the Right Benchmark
| Type of Project | Typical Hurdle Rate (India) |
|---|---|
| Infrastructure (long-term, low-risk) | 10-12% |
| Manufacturing capacity expansion | 13-16% |
| New product launches | 15-20% |
| Real estate development | 15-18% |
| R&D / Innovation | 20-25% |
| Startup / Early-stage | 25-35% |
| VC-backed scale-up | 20-30% |
| Distressed turnaround | 25-40% |
Higher risk demands higher hurdle rate. Most large Indian corporates use WACC (Weighted Average Cost of Capital) as base hurdle, then add risk premium for project-specific factors.
IRR in Real-Life Decisions
- Solar Rooftop: ₹2.5L investment, ₹3K/month savings for 25 years. IRR ≈ 16% — strong accept.
- EV vs Petrol Car: ₹3L premium for EV, ₹50K/year fuel savings + maintenance lower. Over 10 years, IRR ≈ 14%.
- Education Loan Self-Funding: ₹20L education cost, ₹5L/year extra salary post-MBA for 10 years. IRR ≈ 18%.
- Rental Property: ₹1 cr property, ₹30K/month rent, sold at ₹1.5 cr in 10 years. IRR ≈ 7% — barely beats FD; opportunity cost analysis required.
- Franchise Business: ₹50L investment, ₹15L/year profit for 8 years. IRR ≈ 25% — accept if you have operational skill.
How IRR is Computed (Excel Formula)
Excel: =IRR(values, [guess]) — values is an array starting with negative outflow, followed by positive returns. Guess is optional starting estimate (default 10%).
Manual computation: Use trial-and-error or bisection. Start with two rates that give NPV with opposite signs (one +ve, one -ve), then narrow down. Most calculators (BA II Plus, HP 12C) have IRR function built-in.
Frequently Asked Questions
What’s the difference between IRR and ROI?
ROI (Return on Investment) is a simple ratio (Gain/Investment), no time consideration. IRR is annualised return considering time value of money — much more accurate. ROI is useful for quick comparisons; IRR for proper investment decisions.
Can IRR be negative?
Yes — when present value of inflows is less than initial investment. Indicates the project destroys value (loses money in real terms). Should be rejected unless strategic reasons override.
Why does my IRR calculation show #NUM error in Excel?
Three common reasons: (1) All cash flows are same sign, (2) Initial guess is too far from actual IRR — try guess=0.5 or 0.25, (3) The cash flow pattern has no real root. Add a guess parameter.
Is higher IRR always better?
Generally yes, but with caveats: (1) Verify scale matters (₹1L @ 30% vs ₹1 Cr @ 15% — latter creates more wealth), (2) Check reinvestment assumption (use MIRR for high-IRR projects), (3) Account for risk — high IRR often = high risk.
What is MIRR and why is it better?
Modified IRR addresses IRR’s unrealistic reinvestment assumption. MIRR assumes intermediate cash flows earn the cost of capital, not IRR. Excel: =MIRR(values, finance_rate, reinvest_rate). For most real-world decisions, MIRR is more accurate than IRR.
How do I compute IRR for an SIP investment?
Use XIRR, not IRR. SIPs have irregular dates (1st of each month). XIRR handles this; IRR assumes evenly-spaced flows. In Excel: =XIRR(values, dates, [guess]).
What’s a ‘good’ IRR for a small business?
Generally 18-25% for early-stage businesses, 15-20% for established SMEs, 12-15% for large stable businesses. Anything below cost of capital (typically 12-14% for Indian SMEs) is value-destroying.
Should IRR include taxes?
Yes — use after-tax cash flows for after-tax IRR. Compare with after-tax cost of capital. Mixing pre-tax IRR with post-tax cost of capital is a common error.
Can I use IRR for personal investment decisions?
Yes — but XIRR is better for personal investments. IRR is most useful for evaluating evenly-spaced flows (e.g., annual rental income from property, annual ULIP premiums).
What’s the relationship between IRR and NPV?
IRR = the discount rate at which NPV = 0. If IRR > discount rate used in NPV, NPV is positive (accept). If IRR < discount rate, NPV is negative (reject). For most decisions, both methods agree.
How accurate is the bisection method for IRR?
Very accurate — converges within 0.01% accuracy in 50-100 iterations. Newton-Raphson method (used by Excel) is faster but can fail to converge for unusual cash flows. Bisection is reliable but slower.
Is IRR appropriate for measuring fund performance?
For private equity / venture capital funds — YES, IRR is the industry standard. For listed equity mutual funds with SIP — use XIRR. For lumpsum equity investments — use CAGR.