Assumptions and method

When to be cautious

Only one initial outlay followed by nonnegative receipts is supported. Multiple sign changes can create several IRRs. Use NPV to compare different project scales.

NPV(r) = 0

Test a scenario

Use your own inputs

Inputs stay in your browser. Shared scenario links include your inputs.

Use the result in a decision

Use consistent currency, timing and price assumptions.

Only one initial outlay followed by nonnegative receipts is supported. Multiple sign changes can create several IRRs. Use NPV to compare different project scales.

Set a baseline and change one assumption to compare outcomes.

A worked example

Follow the fixed teaching example
  1. Set −12,000 + 4,500/(1+r) + 5,000/(1+r)² + 5,500/(1+r)³ = 0.
  2. The tool brackets and repeatedly bisects the rate until the discounted receipts equal the outlay. Use the resulting rate only for this conventional cash-flow sequence.

These illustrative inputs describe a project scenario, not a published benchmark. All monetary inputs use the same currency and price basis.

Initial outlay
12000
Period-end receipts
4500, 5000, 5500
IRR per period
11.6181 %

Interpret the output only within the assumptions above. Changing the inputs changes the result; it does not validate the inputs.

Source & credit

Standard financial mathematics; no single inventor is asserted.

OpenStax: Principles of Finance, capital budgeting

This is independently written code and explanation of the underlying method. The linked publication, its diagrams and its trademarks remain its owner’s material; no permission to reuse them is implied.

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