Summary

This free IRR calculator returns the internal rate of return for any investment with uneven cash flows. Enter the amount invested, choose years, quarters or months, and add each period's return. It solves the equation where net present value equals zero, then shows the per-period IRR, the annualized rate, the multiple on invested capital and the net gain. It runs in your browser.

Free finance tool

IRR Calculator for Uneven Investment Cash Flows

Enter what you invested and what came back each period. Get the internal rate of return, the annualized rate and the multiple, live.

Calculate IRR

Calculate your internal rate of return

Prefilled with a worked example: 2,000,000 invested, 10,000,000 returned in period 5. Change any number and the result updates.

Enter money returned as positive numbers and follow-on investments as negative numbers. Leave unused periods empty. Any currency works.

IRR per year--
Annualized IRR--
Multiple on invested capital--
Net gain--

How it works

What goes into the IRR number

The equation it solves

IRR is the rate r that makes the sum of CF(t) / (1 + r)^t equal zero, with the amount invested counted as a negative flow at period 0. Nothing else is assumed: no fees, no taxes, no reinvestment schedule.

How the rate is found

There is no closed form for most schedules. The page scans candidate rates for the point where the net present value flips sign, then bisects that bracket 200 times, which pins the rate far below a hundredth of a percent.

Per period versus annualized

With quarterly or monthly flows, the per-period rate is compounded to a yearly figure as (1 + r)^n - 1, where n is 4 or 12. A 10% quarterly IRR is a 46.41% annualized IRR, not 40%.

Worked examples

Same multiple, very different IRR

The time axis is what separates IRR from a plain multiple. These figures come straight from the formula above, so you can reproduce each one in the calculator.

  • 2M invested, 10M back in year 5 (5.0x): 37.97% IRR
  • 3.0x returned in year 5: 24.57% IRR
  • 3.0x returned in year 3: 44.22% IRR
  • 10.0x returned in year 10: 25.89% IRR
Pen pointing at a printed cash flow schedule on a desk
Method

Run an IRR check in four steps

  1. 1

    Set the amount invested

    Type the capital you put in at period 0 as a positive number. The calculator treats it as an outflow.

  2. 2

    Choose the period length

    Pick years, quarters or months so the flows are evenly spaced. Equal spacing is a requirement of the standard IRR.

  3. 3

    Fill in cash flows

    Enter distributions, exits or dividends as positive numbers in the period they arrive. Enter follow-on investments as negative numbers.

  4. 4

    Read three numbers together

    Look at the IRR, the annualized rate and the multiple on invested capital. A high IRR with a low multiple means a fast but small win.

FAQ

IRR calculator questions

What does the IRR calculator compute?
It finds the single discount rate at which the net present value of your cash flows equals zero. That rate is the internal rate of return, shown per period and annualized for quarterly or monthly schedules.
Is the IRR calculator free, and is my data stored?
It is free and needs no signup. The calculation runs in your browser, so the amounts you type are not sent to a server. Only an anonymous tool-run counter is recorded.
Which formula does it use?
It solves the sum of CF(t) / (1 + r)^t = 0 for r, where CF(0) is the amount invested as a negative number. It scans rates from -99% upward for a sign change, then narrows the bracket by bisection until the value is stable.
How is this different from Excel IRR and XIRR?
Excel IRR assumes equally spaced periods, which is what this page does. XIRR uses actual calendar dates, so it fits irregular dates. If your flows land on exact dates, use XIRR; for annual, quarterly or monthly schedules, the results match.
Why does it say no IRR exists?
IRR needs at least one outflow and one inflow. If every flow has the same sign, no rate can bring the net present value to zero. Check that the invested amount is positive here and that returns are entered as positive numbers.
What happens with several follow-on rounds or reinvestments?
A schedule that flips sign more than once can have more than one valid IRR. The calculator returns the lowest rate that solves the equation and warns you when the schedule has multiple sign changes.
How do I read the multiple on invested capital?
It divides total cash returned by total cash invested, including negative follow-on flows. A 5x multiple over 10 years and a 5x multiple over 3 years look identical there, while IRR separates them.
Does IRR assume I can reinvest at the same rate?
IRR implicitly treats interim cash as reinvested at the IRR itself, which can overstate results for very high rates. For a conservative check, compare against the multiple on invested capital.

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