NPV Calculator
NPV Calculator works out Net present value and Profitability index from Cash flows, first period first, Discount rate per period and Present value of the future inflows. The default figures on this page give net present value of 16,986.54; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
9 steps
- Discount factor for period t = 1 / (1 + 0.1)^t, so period 0 is undiscounted.
- t=0: -100000 x 1 = -100000 (running total -100000).
- t=1: 30000 x 0.90909091 = 27272.7273 (running total -72727.2727).
- t=2: 35000 x 0.82644628 = 28925.6198 (running total -43801.6529).
- t=3: 40000 x 0.7513148 = 30052.592 (running total -13749.0609).
- t=4: 45000 x 0.68301346 = 30735.6055 (running total 16986.5446).
- NPV = 16986.544635.
- The IRR is the rate that drives this same sum to zero: 17.093686% a period.
- Profitability index = PV of inflows / PV of outflows = 116986.5446 / 100000 = 1.169865.
Period-by-period discountingtable
| period | cashFlow | discountFactor | presentValue | cumulativePresentValue |
|---|---|---|---|---|
| 0 | -100,000 | 1 | -100,000 | -100,000 |
| 1 | 30,000 | 0.909091 | 27,272.727273 | -72,727.272727 |
| 2 | 35,000 | 0.826446 | 28,925.619835 | -43,801.652893 |
| 3 | 40,000 | 0.751315 | 30,052.592036 | -13,749.060856 |
| 4 | 45,000 | 0.683013 | 30,735.605491 | 16,986.544635 |
Its 5 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
2 sources
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What the NPV Calculator calculates
Discounts a series of equally spaced cash flows at a constant periodic rate to give net present value, and with it the internal rate of return, the profitability index and the discounted payback period.
How to use this NPV Calculator
Enter Cash flows, first period first, Discount rate per period, Present value of the future inflows and Initial investment. Net present value updates as you type, and “Use a worked example” loads checked figures you can adjust. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Net present value, Profitability index and Present value of inflows.
The method follows Brealey, Myers & Allen, Principles of Corporate Finance, ch. 2 and 5 - the net present value rule and the definition NPV = sum CF_t/(1+r)^t with CF_0 undiscounted and US Office of Management and Budget Circular A-94, Guidelines and Discount Rates for Benefit-Cost Analysis of Federal Programs, appendix B - present value and discount factor definitions.
Research fixture R4260-GT-5: [-100, 50, 60] at -5% a period example
With What do you have?: cash-flows, Cash flows, first period first: -100,50,60, Discount rate per period: -5, the calculator returns Net present value: 19.1135734. This example is checked against an independent source in the test suite.
What you can compare
Change one input at a time to see how it affects Net present value, Profitability index and Present value of inflows. The inputs you can vary are Cash flows, first period first, Discount rate per period, Present value of the future inflows and Initial investment.
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
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Frequently asked questions
How to get NPV on calculator?
Discounts a series of equally spaced cash flows at a constant periodic rate to give net present value, and with it the internal rate of return, the profitability index and the discounted payback period. Open “How this is worked out” beside the result to see each step for your own figures.
How can I calculate the NPV?
It needs Cash flows, first period first, Discount rate per period, Present value of the future inflows and Initial investment. Nothing else is required, and the figures stay in your browser.
How to enter NPV on a TI-84?
The result gives Net present value, Profitability index, Present value of inflows, Present value of outflows, Internal rate of return and Discounted payback (periods), each labelled with its unit so the figure can be read on its own.
What is the NPV golden rule?
On the figures this page opens with — discount rate per period -5% — the net present value is 16,986.54. No single number fits everyone: change any figure above and the answer updates as you type, with each step of the arithmetic beside it.
What information do I need for the NPV Calculator?
You need Cash flows, first period first, Discount rate per period, Present value of the future inflows and Initial investment. The page opens with default figures that give net present value of 16,986.54, so you can see the scale before entering your own.
What does this NPV Calculator show?
It shows Net present value, Profitability index, Present value of inflows, Present value of outflows, Internal rate of return, Discounted payback (periods), Sum of the undiscounted flows and NPV rule, with the working and any warnings for your entries.