Formula and calculation method
IRR solves Σ cash flow at t / (1 + r)^t = 0 for equal periods.
Scans for a bracketed root; cash flows with multiple sign changes can have multiple IRRs. Only the first discovered root is reported.
How to use irr calculator
- Set Equal-period cash flows (outlay first). The example below uses -10000, 3000, 4000, 5000.
- Select Calculate to update the result. Reset restores the illustrated inputs. Copy, print or download your own result if you need a record.
Worked example
Example inputs
- Equal-period cash flows (outlay first)
- -10000, 3000, 4000, 5000
- Internal rate of return per period (%)
- 8.89633947
Factors affecting your result
Scans for a bracketed root; cash flows with multiple sign changes can have multiple IRRs. Only the first discovered root is reported.
Changing equal-period cash flows (outlay first) changes the scenario being evaluated. Adjust one input at a time when comparing results, keep a copy of the assumptions, and compare values using the same unit and period. A precise arithmetic result does not make an uncertain assumption precise.
Frequently asked questions
How does the irr calculator work?
IRR solves Σ cash flow at t / (1 + r)^t = 0 for equal periods.
What inputs does IRR Calculator need?
Enter equal-period cash flows (outlay first). Choose values that correspond to the same situation and measurement convention.
How should I interpret the irr calculator result?
Scans for a bracketed root; cash flows with multiple sign changes can have multiple IRRs. Only the first discovered root is reported.
Are my irr calculator inputs uploaded?
No. The calculation runs in this browser. Favorites, recent tool names, theme and formatting preferences may be saved locally, but calculation inputs are not sent to a calculation server or stored by this website. Shared links do not include entered values.
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