Calculate the Internal Rate of Return (IRR) for an investment based on an initial outlay and a series of future cash flows.
The Internal Rate of Return (IRR) is the discount rate that makes the Net Present Value (NPV) of all cash flows equal to zero. It's the annualized rate of return an investment is expected to generate, used to compare projects or investments with different cash flow timings.
Where CFₜ is the cash flow in period t, including the initial investment as a negative value at t=0. There's no closed-form algebraic solution, so IRR is found by testing rates iteratively (as this calculator does) until NPV reaches zero.
An initial investment of $10,000 that returns $3,000/year for 5 years has an IRR of roughly 15.2% — meaning the investment performs as if it earned a steady 15.2% annual return.
What's a good IRR? It depends on the investment type and risk — many investors compare IRR against their required rate of return or cost of capital; higher isn't automatically better if it comes with much higher risk.
What's the difference between IRR and ROI? ROI measures total return over the whole period without accounting for timing, while IRR annualizes the return and accounts for when each cash flow occurs.
Can IRR be negative? Yes — a negative IRR means the investment is expected to lose money overall, with cash inflows not enough to recover the initial outlay.
Why do some investments have multiple IRRs? When cash flows switch sign more than once (e.g., negative, positive, then negative again), the NPV equation can have more than one valid solution, making a single IRR ambiguous.
Is IRR calculator for rental property useful for real estate? Yes — real estate investors often use IRR to compare a property's purchase price, annual net cash flow, and eventual sale proceeds against other investment opportunities.
An investment is attractive when its IRR is higher than the return you require, often called the hurdle rate. That hurdle might be the interest rate on a loan used to finance the project, the return from a safe alternative, or a target that reflects the risk. If the IRR clears the hurdle, the project adds value under your assumptions; if not, you may do better elsewhere.
| Limitation | What it means |
|---|---|
| Reinvestment assumption | IRR implicitly assumes interim cash flows are reinvested at the same rate, which can be optimistic for very high IRRs. |
| Ignores scale | A small project can have a high IRR but create less total value than a large one. |
| Timing sensitivity | Receiving money earlier increases IRR even if the total is the same. |
| Unusual cash flows | Flows that switch between positive and negative can produce several IRRs or none. |
For these reasons, analysts often use IRR alongside net present value (NPV) rather than instead of it.
Is IRR the same as the annual return I will actually earn? Only if the cash flows happen exactly as modelled and you can reinvest at the same rate. Real results usually differ.
When should I use NPV instead? NPV is better for comparing projects of different sizes and for situations with unconventional cash flows, because it measures value in money rather than as a rate.