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Internal Rate of Return (IRR) Calculator

Find the internal rate of return — the discount rate at which a project's NPV is zero — from a list of cash flows. Enter the initial investment as a negative first value. Calculated in your browser.

  • 100% free
  • Private & safe
  • Runs in your browser

Why use IRR Calculator?

IRR Calculator gives you accurate results instantly, with the underlying formula shown so you can trust the numbers.

  • Runs instantly in your browser — nothing to install, nothing uploaded.
  • Completely free, with no account, no watermarks and no usage limits.
  • IRR is the rate where NPV = 0, found numerically.
  • List the cash flows, year 0 first.
  • Works on any device — desktop, tablet and phone — and is fully keyboard accessible.

How to use IRR Calculator

  1. List the cash flows, year 0 first.
  2. Include a negative initial investment.
  3. See the IRR percentage.
  4. Compare against your hurdle rate.

Examples

  • -1000 then 300,400,500,600 → IRR.
  • Checking if a project beats a 10% hurdle.

Formulas

  • IRR is the rate where NPV = 0, found numerically.

Limitations

  • Needs at least one sign change; unusual flows can have multiple IRRs.
  • Estimate only, not financial advice.

Frequently asked questions

Why can't it find an IRR?

Without a sign change (e.g., a negative then positives) IRR is undefined.

Annual periods?

Yes — each value is one period.

Stored?

No — local only.

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