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IRR Calculator

Solve for the internal rate of return on an initial investment and a series of period cash flows, with a plain readout when no solution exists.

Investment and required return

Period cash flows

Year 1
Year 2
Year 3
Year 4

Paste several values at once, one per line, into any field to fill the list. Everything runs in your browser.

Internal rate of return
18.03%
per year, clears the required return of 8%
0.00
Net present value at that rate
10,000.00
Initial investment

Assumes each cash flow lands at the end of its period. The rate found is the one that makes net present value zero for the exact cash flows entered.

How to calculate internal rate of return

  1. Enter the initial investment

    Type the upfront cost of the project and, if you have one, a required return to check the result against.

  2. Add each period’s cash flow

    Fill in the cash flow expected in each period. Use Add period for more rows, or paste a column of values copied from a spreadsheet into any field.

  3. Read the internal rate of return

    The tool solves for the rate that brings net present value to zero and shows it instantly, along with net present value at that rate as a check.

  4. Compare against your required return

    If a required return was entered, the result also states plainly whether the project clears it.

Why use this tool

Robust rate solving

A wide search finds a bracket around the rate where net present value hits zero, then narrows it down with a capped number of steps so the calculation always finishes.

Plain no-solution readout

When the cash flows never change sign, or when no rate in the search range works, the tool says so directly instead of returning a wrong number.

Multiple sign change warning

If the cash flows change sign more than once, the tool warns that another rate could also satisfy the equation and reports the one it found.

Net present value sanity check

Net present value at the rate found is shown alongside it, which should sit at or very near zero and confirms the solve worked.

Editable cash flow list

Add or remove periods freely, and paste a column of values copied from a spreadsheet into any field to fill several rows at once.

Private by design

Every figure you enter is calculated in your browser. Nothing is uploaded or stored.

About this tool

The internal rate of return is the discount rate at which a project’s net present value hits exactly zero: the rate at which the discounted future cash flows exactly balance the initial investment. This tool solves for that rate given an initial cost and a series of period cash flows, then reports it as a percentage alongside the net present value at that rate, which should land at or very near zero as a check on the working.

Real-world cash flow patterns are not always well behaved for this kind of solve. If the cash flows never change sign, for example an investment that only ever pays out, or one that only ever costs money, there is no rate that can bring net present value to zero, and the tool says so rather than guessing. If the cash flows change sign more than once, more than one rate can technically satisfy the equation, and the tool warns about this while still reporting the rate it found closest to zero. Entering a required return alongside the cash flows shows plainly whether the project clears the bar you have set for it.

Everything runs in your browser, so the figures you enter are never uploaded or stored. To see the net present value at a rate you choose yourself, along with a full per-period discount schedule, use the npv calculator; for a simple lump-sum return without period-by-period cash flows, use the roi calculator.

Frequently asked questions

What is the internal rate of return?
It is the discount rate at which a project’s net present value equals zero. In other words, it is the annualized return the cash flows imply, found by solving the net present value equation for the rate instead of the result.
How does the tool find the rate?
It scans a wide, fixed range of candidate rates to find two where net present value changes sign, then narrows that bracket with repeated halving, capped at a fixed number of steps so the calculation always finishes quickly.
What if there is no solution?
If the cash flows never change sign, for example an investment that only pays out or only costs money, no rate can bring net present value to zero, and the tool states this plainly rather than showing a misleading number.
What does the multiple sign change warning mean?
When cash flows switch between positive and negative more than once, more than one rate can technically make net present value zero. The tool reports the rate it found and flags that another one may also work, since which one is "correct" depends on context the tool cannot know.
Are the figures I enter kept private?
Yes. The whole calculation runs in your browser. The investment amount, the required return, and every cash flow you enter are never uploaded, stored, or logged.

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