Finance Calc Kit

Year	Cash flow	Cumulative
1	$2,500.00	-$7,500.00
2	$2,500.00	-$5,000.00
3	$2,500.00	-$2,500.00
4	$2,500.00	$0.00
5	$2,500.00	$2,500.00
6	$2,500.00	$5,000.00
7	$2,500.00	$7,500.00
8	$2,500.00	$10,000.00
9	$2,500.00	$12,500.00
10	$2,500.00	$15,000.00

Year	Discounted CF	Cumulative
1	$2,272.73	-$7,727.27
2	$2,066.12	-$5,661.16
3	$1,878.29	-$3,782.87
4	$1,707.53	-$2,075.34
5	$1,552.30	-$523.03
6	$1,411.18	$888.15
7	$1,282.90	$2,171.05
8	$1,166.27	$3,337.32
9	$1,060.24	$4,397.56
10	$963.86	$5,361.42

What is payback period?

Payback period is the time required to recover an initial investment from the cash flows a project generates. It is one of the simplest capital budgeting metrics and is widely used to screen projects for liquidity risk and speed of capital recovery. A shorter payback period generally signals faster recovery, while a longer payback period implies more uncertainty about when invested capital is returned.

For example, a $10,000 investment that returns $2,500 per year has a payback period of 4 years. This calculator also computes discounted payback period, which adjusts future cash flows for the time value of money, and net present value (NPV) at your chosen discount rate. For IRR-based hurdle rate analysis, use the IRR calculator. For direct NPV valuation with flexible compounding and timing, use the net present value calculator.

Simple payback period formula

With equal annual cash inflows, simple payback divides the initial investment by the annual cash flow. When cash flows vary by year, accumulate inflows until cumulative cash flow reaches zero (full recovery). Fractional years are interpolated linearly within the recovery year.

\mathrm{Payback\ Period} = \frac{\mathrm{Initial\ Investment}}{\mathrm{Annual\ Cash\ Flow}} \quad \text{(equal annual flows)}

For uneven cash flows, find the year $n$ where cumulative inflows first cover the initial outlay, then add the fractional portion of year $n$ needed to reach breakeven:

\mathrm{Payback} = (n - 1) + \frac{|\mathrm{Cumulative\ at\ } n-1|}{\mathrm{Cash\ Flow}_n}

Discounted payback period and NPV

Simple payback ignores the time value of money. Discounted payback period corrects this by discounting each future cash flow before accumulating them. The discount rate is typically your weighted average cost of capital (WACC), hurdle rate, or opportunity cost of capital.

\mathrm{Discounted\ CF}_t = \frac{\mathrm{CF}_t}{(1 + r)^t}

Net present value sums all discounted cash flows minus the initial investment. A positive NPV means the project earns more than the required return at rate $r$; a negative NPV means it falls short.

\mathrm{NPV} = -I_0 + \sum_{t=1}^{n} \frac{\mathrm{CF}_t}{(1 + r)^t}

Fixed vs irregular cash flows

Fixed cash flow mode models a constant annual inflow with an optional growth rate over a set number of years. This is useful for steady-service contracts, annuity-like returns, or simplified screening. Irregular cash flow mode lets you enter a different amount for each year, which better reflects real projects where returns ramp up, decline, or vary by phase.

Investopedia-style worked example

An initial investment of $10,000 with fixed annual cash inflows of $2,500 recovers capital in exactly 4 years:

\mathrm{Payback} = \frac{10{,}000}{2{,}500} = 4\ \text{years}

Cumulative cash flow reaches zero at the end of year 4: after year 3 the balance is negative $2,500, and the year 4 inflow of $2,500 brings cumulative cash flow to $0. At a 10% discount rate, discounted payback takes longer because early cash flows are worth less in present value terms.

Strengths and limitations

Strength: Easy to explain and compute; useful for liquidity-focused decisions and risk screening.
Strength: Discounted payback incorporates the time value of money, improving long-horizon comparisons.
Limitation: Simple payback ignores cash flows after recovery and does not measure total profitability.
Limitation: Neither version captures project scale or absolute dollar value added; pair with NPV or IRR for fuller analysis.

Frequently asked questions

What is a good payback period?

A good payback period depends on industry, risk, and capital constraints. Many businesses prefer payback within 3 to 5 years for moderate-risk projects, but capital-intensive industries may accept longer horizons. Compare against your firm's hurdle and peer benchmarks.

What is the difference between payback period and discounted payback period?

Simple payback treats all future dollars equally. Discounted payback discounts each cash flow to present value before accumulating, so it takes longer when the discount rate is positive. Discounted payback is more accurate for long-term projects.

What discount rate should I use?

Use your weighted average cost of capital (WACC), a project-specific hurdle rate, or the return you could earn on the next best alternative investment. Higher-risk projects warrant a higher discount rate.

How does growth rate affect payback?

In fixed mode, a positive annual growth rate increases later-year cash flows, which can shorten payback if growth is meaningful. Zero growth produces equal annual inflows and the simplest payback calculation.

Can payback period be longer than the forecast horizon?

Yes. If cumulative cash flows never reach zero within the years you model, the investment is not recovered in that horizon. Extend the forecast, increase inflows, or reduce the initial outlay to explore alternatives.

Are results stored on your servers?

No. All calculations run in your browser. Changing inputs updates the page URL so you can bookmark or share your scenario.

Resources and references

The formulas and methods in this calculator were checked against these independent sources.

Payback Period Calculator

Investment inputs

Payback schedule

Discounted payback schedule