What does the IRR Calculator actually compute?

The IRR Calculator solves for the internal rate of return — the discount rate at which the net present value of your entered cash flows equals zero — and also reports NPV at a discount rate you choose.

How does the IRR Calculator handle cash flows with no valid IRR?

If every cash flow you enter is positive, or every one is negative, there is no rate that zeroes out NPV, so the IRR Calculator reports 'no solution' instead of a misleading number.

Can the IRR Calculator use uneven cash flows across different years?

Yes. Each row is one period's cash flow and they do not need to match a pattern — the calculator solves IRR numerically for any mix of positive and negative amounts.

What discount rate should I use for the NPV Calculator field?

Use your required rate of return or cost of capital. The IRR Calculator does not choose this for you; it simply shows the NPV that results from the rate you enter.

Is the IRR Calculator's output financial advice?

No. The IRR and NPV figures are estimates based only on the numbers you enter — not financial advice. Verify any real investment decision with a qualified professional.

IRR Calculator Online

Compute the internal rate of return and net present value from a series of cash flows, right in your browser. Estimates only — not financial advice.

The IRR Calculator runs entirely in your browser. The cash flows and discount rate you enter never leave your device, and nothing is uploaded to ArrayKit. Results are estimates only, not financial advice.

Open the Present Value Calculator

About IRR Calculator

IRR Calculator finds the internal rate of return and net present value (NPV) for a series of cash flows, from an initial outflow to any number of later inflows or outflows. Enter each period's cash flow — year 0 is typically the negative initial investment — and the calculator solves for the discount rate at which NPV equals zero, then shows the NPV at a discount rate you choose. It is useful when comparing projects, evaluating a business investment, or checking whether a deal clears your required return. Built for analysts, small-business owners, and students who want a fast IRR and NPV read without opening a spreadsheet. All the math runs locally in your browser and figures never leave your device. These are estimates only, not financial advice — verify any investment decision with a qualified professional.

Features

Editable list of cash flows, starting with the year-0 initial outflow
Solves IRR by bisection so it works for uneven, multi-year cash flows
Computes NPV at any discount rate you enter
Add or remove cash-flow rows up to a generous row cap
Clear warning when no IRR exists for the entered series
Copy a plain-text summary of the cash flows, IRR, and NPV
Accepts thousands separators and currency symbols in each field
Runs entirely in your browser — no cash-flow figures are uploaded

How to use the IRR Calculator

Enter the initial outflow in Year 0 as a negative number
Add a row for each following period's cash flow (positive or negative)
Set the discount rate to see NPV at that rate
Read the IRR and NPV results, and copy the summary if needed

Example

Input

-1000, 500, 500, 500

Output

IRR: 23.38%

Common errors & troubleshooting

IRR shows 'No solution' for a valid-looking project. — IRR requires at least one negative and one positive cash flow. If every entered value is positive (or every value is negative), add the missing initial outflow or a later return.
Discount rate entered as a whole number produces an unexpected NPV. — Enter the discount rate as a percentage, e.g. 10 for 10%, not 0.10 — the IRR Calculator multiplies by 100 internally.
NPV looks too small compared to the raw sum of cash flows. — NPV discounts each future cash flow back to today, so later payments count for less than the same amount today at a positive discount rate.
Two different discount rates give very different investment rankings. — This is expected — NPV depends heavily on the chosen discount rate. Compare projects at the same rate, or rely on IRR, which does not require picking a rate.

Frequently asked questions

What does the IRR Calculator actually compute?: The IRR Calculator solves for the internal rate of return — the discount rate at which the net present value of your entered cash flows equals zero — and also reports NPV at a discount rate you choose.
How does the IRR Calculator handle cash flows with no valid IRR?: If every cash flow you enter is positive, or every one is negative, there is no rate that zeroes out NPV, so the IRR Calculator reports 'no solution' instead of a misleading number.
Can the IRR Calculator use uneven cash flows across different years?: Yes. Each row is one period's cash flow and they do not need to match a pattern — the calculator solves IRR numerically for any mix of positive and negative amounts.
What discount rate should I use for the NPV Calculator field?: Use your required rate of return or cost of capital. The IRR Calculator does not choose this for you; it simply shows the NPV that results from the rate you enter.
Are my cash-flow numbers uploaded anywhere?: No. The IRR Calculator runs entirely in your browser. The cash flows and discount rate you enter never leave your device and nothing is sent to ArrayKit.
Is the IRR Calculator's output financial advice?: No. The IRR and NPV figures are estimates based only on the numbers you enter — not financial advice. Verify any real investment decision with a qualified professional.

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ROI Calculator — Calculate return on investment, net gain and annualized ROI.
Present Value Calculator — Find the present value of a future sum or cash flow stream at a discount rate.
Payback Period Calculator — Find how long an investment takes to pay back from its cash flows.
Investment Calculator — Solve for the ending amount, return, contribution or time of an investment.
Future Value Calculator — Find the future value of a present sum or a stream of payments.
CAGR Calculator — Calculate the compound annual growth rate and average return of an investment.