Free calculator
IRR calculator
Enter what you invest today and the cash it returns each period, or paste the column from a spreadsheet. You get the internal rate of return, its annual equivalent, and the Excel formula that should give the same answer.
Project
Your required return or cost of capital, for one period.
Enter it as a positive number; it's treated as cash out.
Use a minus sign for a cash outflow, such as a later reinvestment.
MIRR rates (optional)
Blank uses the discount rate.
Blank uses the discount rate.
Discounted cash flows
| Year | Cash flow | Present value | Cumulative PV |
|---|---|---|---|
| 0 | (100,000.00) | (100,000.00) | |
| 1 | 25,000.00 | (77,272.73) | |
| 2 | 30,000.00 | (52,479.34) | |
| 3 | 35,000.00 | (26,183.32) | |
| 4 | 30,000.00 | (5,692.92) | |
| 5 | 25,000.00 | 9,830.12 | |
| Net present value | 9,830.12 | ||
Check it in Excel or Google Sheets
With the initial investment in B2 as a negative number and the cash flows in B3:B7:
=NPV(10%, B3:B7) + B2- $9,830.12
=IRR(B2:B7)- 13.75%
Leave B2 out of the NPV range. Excel’s NPV function discounts the first value it’s given by one full period, so including today’s investment understates the result.
What IRR tells you
The internal rate of return is the discount rate at which a project’s net present value is exactly zero. Put another way, it’s the rate the investment earns on the money still tied up in it, period by period.
The calculator’s starting example invests $100,000 and gets back $25,000, $30,000, $35,000, $30,000 and $25,000 over five years. Its IRR is 13.75%. Discount the same cash flows at 13.75% and they are worth $0 net of the investment, which is the test that the rate is right. At a 10% hurdle rate the NPV is $9,830, positive because the IRR is above 10%.
There’s no formula that solves for IRR directly once there are more than a couple of periods, so it is found by trial: try a rate, see whether NPV is above or below zero, and narrow in. The calculator brackets the answer between −99% and 10,000% and halves the gap until NPV is within a fraction of a cent of zero.
IRR in Excel
Select the whole column, investment included, as values: unlike Excel’s NPV function, IRR expects the first value to be today’s cash flow. Microsoft’s documentation says the values must include at least one positive and one negative number, that IRR starts from a guess of 10% if you leave the second argument out, and that it returns #NUM! if it hasn’t found a rate accurate to 0.00001% after 20 tries.
When the cash flows fall on irregular dates, use =XIRR(values, dates), which returns an annual rate. The calculator prints the matching Excel formula next to each result, so you can check a workbook against it.
When IRR misleads
The cash flows change sign more than once
Each change from cash out to cash in, or back, can add another rate that sets NPV to zero. A project that costs $1,000, returns $2,500, then costs $1,540 to wind down has IRRs of 10% and 40%. Neither is wrong, and neither is much use. The calculator warns you when the signs change more than once; rely on NPV at your discount rate instead.
Comparing projects of different size or timing
A small project can have a higher IRR than a large one and still add fewer dollars of value. When you must choose one of two, rank them by NPV at your discount rate, not by IRR.
The reinvestment question
IRR implicitly values interim cash as if it earns the IRR itself. Modified IRR (MIRR) replaces that with rates you choose: one for financing outflows and one for reinvesting inflows. For the starting example, MIRR at 10% for both is 12.08%. Set your own rates in the calculator’s optional fields.
Prefer an amount to a rate? The NPV calculator uses the same inputs and leads with net present value. For how long the money takes to come back, see the payback period calculator.
IRR: questions
- What is a good IRR?
- One that beats the return you require for the risk, usually your cost of capital or a hurdle rate your firm sets. If a project's IRR is above that rate, its NPV at that rate is positive. There's no single good number: a rate that is ample for a low-risk equipment purchase can be thin for a new venture.
- How do I convert a monthly IRR to an annual rate?
- Compound it: (1 + monthly IRR)^12 − 1. A 1% monthly IRR is 12.68% a year, not 12%. For quarterly periods, raise to the 4th power. The calculator shows the annual rate when you set the period to a month or a quarter.
- Why does Excel's IRR return #NUM!?
- Microsoft's documentation gives two causes. The values must include at least one negative and one positive cash flow, and IRR gives up with #NUM! if it can't find a rate within 20 iterations. For the second, try a guess closer to the answer as IRR's second argument.
- Can IRR be negative?
- Yes. If the cash flows you get back add up to less than the investment, the rate that sets NPV to zero is below 0%. The calculator reports it like any other rate.
- What's the difference between IRR and XIRR?
- IRR assumes the cash flows are evenly spaced, one period apart. XIRR takes a date for each cash flow and returns an annual rate, so it suits irregular timing, such as a fund with capital calls and distributions on different days.
- Is IRR the same as ROI?
- No. A simple return on investment compares total gain with cost and ignores when the cash arrives. IRR accounts for timing: two projects with the same total gain have different IRRs if one pays back sooner.
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Sources
Official documents read on November 5, 2026. Vendor facts are sourced on each listing.