Find a unique periodic discount rate at which two projects have equal NPV.
It makes the prices, cash flows, rates, time periods, weights, and model conventions explicit so you can inspect an entered scenario without hidden live-market assumptions.
Calculation structure
Follow the stated model and units
Solve NPV(project A cash flows − project B cash flows) = 0 for 1+rate from 1e−14 through 11.
Visual explanation
See how the inputs become the result
Capital and cash flowstime and rate→entered modelScenario resultChanging one assumption changes the model—not the marketSolve NPV(project A cash flows − project B cash flows) = 0 for 1+rate from 1e−14 through 11.
Read the estimate correctly
Use the result within its boundaries
Enter each period's Project A and Project B cash flows in one row.
Cash flows are equally spaced. Multiple roots are rejected, and numerically ambiguous shallow or closely spaced roots return an explicit reliability error.
Quick guide
How to use this calculator
Enter the cash flows, values, rates, timing, or portfolio assumptions named in the fields.
Use one consistent period and currency convention throughout the scenario.
Read the calculator-specific model limits before interpreting the result.
Calculation method
Calculation method
Solve NPV(project A cash flows − project B cash flows) = 0 for 1+rate from 1e−14 through 11.
Model, simulation, root, square-root, and compounding outputs are estimates and are visibly marked approximate.
Worked example
Worked example
Enter each period's Project A and Project B cash flows in one row.
Solve NPV(project A cash flows − project B cash flows) = 0 for 1+rate from 1e−14 through 11.
Supported inputs
Precision and limits
Visible input limits
Inputs support up to 12 decimal places and lists support at most 1,200 rows. Iteration and simulation bounds are displayed in their fields.
International scope
No exchange, tax system, reporting standard, currency, fund rule, trading calendar, or market convention is selected automatically.
Decision boundary
Outputs are entered scenarios, not valuations, forecasts, risk limits, executable trades, suitability decisions, or recommendations.
Calculator-specific assumptions
Cash flows are equally spaced. Multiple roots are rejected, and numerically ambiguous shallow or closely spaced roots return an explicit reliability error.
