Internal Rate of Return Calculator

How to use

Internal rate of return is the periodic discount rate that makes the net present value of a periodic cash-flow series equal zero. Some cash-flow patterns can have more than one valid rate, so this calculator searches for multiple roots rather than assuming IRR is always unique.

1. Enter CF0, CF1, CF2… with their real signs, separated by commas or lines.
2. At least one positive and one negative cash flow are required, with no more than 40 values.
3. Calculate to display each IRR root found in the search interval from -99.9999% up to a decimal rate of 1,000,000.

How it is calculated

Example

Example: -1000, 400, 400, 400 gives a periodic IRR of about 9.70%. Cash flows with multiple sign changes can produce more than one root.

Important notes

This is a mathematical tool, not investment advice. It assumes equal periods and does not use actual dates, so it is not XIRR. A real root may not exist in the search range, and multiple roots are possible; interpret IRR alongside NPV and project assumptions.

Frequently asked questions