See how long until an investment pays for itself, with even or uneven yearly cash flows.
Enter the initial investment and the annual cash inflow — or switch to uneven mode and enter up to 5 individual yearly cash flows.
Formula: Even flows: Payback = Investment ÷ Annual inflow. Uneven: accumulate yearly flows until the investment is recovered. Example: $50,000 ÷ $15,000/year → 3.33 years.
The payback period answers the simplest question in investing: how long until I get my money back? The calculator above handles both steady and irregular cash flows. Follow these steps to get an accurate answer.
Pro tip: payback ignores everything after the break-even point, so never use it as your only decision tool. Pair it with the IRR or NPV to check whether the project is merely fast or genuinely profitable.
The payback period is the length of time required for an investment’s cumulative cash flow to equal its initial cost. It marks the break-even point in time: before payback, the project is still in the red; after payback, every additional dollar is profit. Of all investment metrics, it is the easiest to explain to a non-financial audience, which is why it survives in boardrooms despite its theoretical flaws.
Payback is fundamentally a risk and liquidity measure rather than a profitability measure. A project that pays back in 2 years returns your cash quickly, letting you redeploy it or survive if conditions change. A project with a 9-year payback keeps your capital locked up and exposed to a decade of uncertainty. For small businesses and startups where cash is survival, this liquidity perspective often matters more than squeezing out the last dollar of theoretical value.
The classic version, the simple payback period, ignores the time value of money: it treats $15,000 received in year four as equal to $15,000 received in year one. The refined version, the discounted payback period, discounts each future inflow at the cost of capital before accumulating, so distant cash counts for less. Discounted payback is always longer than simple payback for the same project, and the gap widens as the discount rate rises or the payback stretches further out.
Payback’s famous blind spot is that it ignores all cash flows after the break-even point. A project that pays back in 2 years and then earns nothing looks better on payback than a project that pays back in 4 years and then earns millions for a decade, even though the second project is far more valuable. This is why finance textbooks insist payback should screen projects for risk, never rank them for value: use it to reject the dangerously slow, then choose among the survivors with NPV or IRR.
Used in its proper role, the payback period is a fast, intuitive first filter: it tells you how long your money is at risk, in plain years and months, before you commit to deeper analysis.
For even annual cash flows, the formula is simple division:
Payback period = Initial investment / Annual cash inflow
For uneven cash flows, accumulate the inflows year by year until the cumulative total first reaches the investment, then interpolate within the recovery year:
Payback = A + (B / C)
where A is the number of full years before recovery, B is the unrecovered amount at the start of the recovery year, and C is the cash inflow during the recovery year. The two worked examples below apply these formulas with real numbers.
Worked example 1: even cash flows. You invest $50,000 in a vending machine route that generates $15,000 per year after expenses. Payback = $50,000 / $15,000 = 3.333 years. The 0.333 of a year is 0.333 x 12 = 4 months, so the payback period is 3 years and 4 months. Check: after 3 years you have recovered $45,000, leaving $5,000, which the $15,000 fourth-year inflow covers in $5,000 / $15,000 = one-third of a year. This matches the calculator’s default result exactly.
Worked example 2: uneven cash flows. You invest $50,000 in a small business with expected net inflows of $10,000 in Year 1, $14,000 in Year 2, $18,000 in Year 3, $20,000 in Year 4, and $22,000 in Year 5. Accumulate: after Year 1, $10,000; after Year 2, $24,000; after Year 3, $42,000; after Year 4, $62,000, which first reaches the $50,000 investment. So A = 3 full years, B = $50,000 – $42,000 = $8,000 unrecovered, and C = $20,000. Payback = 3 + ($8,000 / $20,000) = 3 + 0.4 = 3.4 years, or 3 years and 4.8 months (about 3 years and 5 months). Notice the uneven pattern pays back slightly slower than the even $15,000-per-year case, because the early years are leaner.
The pattern is always the same: stack up the inflows until they cover the investment, then measure the fraction of the final year needed. The calculator above automates the stacking and the interpolation for you.
A restaurant owner considers a $50,000 wood-fired pizza oven, including installation and staff training. The oven is expected to generate $16,000 per year in additional net cash flow: extra pizza sales minus the cost of ingredients, gas, and the additional labor hour per day.
Payback = $50,000 / $16,000 = 3.125 years, which is 3 years and 1.5 months (0.125 x 12 = 1.5). The owner’s rule is that equipment must pay back within 4 years, so the oven passes the screen comfortably, with nearly a year to spare.
But the owner stress-tests the numbers. If pizza sales disappoint and the oven generates only $12,000 per year, payback stretches to $50,000 / $12,000 = 4.167 years, or 4 years and 2 months, which fails the 4-year cutoff. If sales beat expectations at $20,000 per year, payback shrinks to 2.5 years. This range, 2.5 to 4.17 years, frames the real decision: the oven is attractive if the owner believes the $16,000 estimate is conservative, and questionable if it is optimistic. The payback calculation took seconds; the judgment about the cash flows is where the real work lies.
Simple payback treats future dollars as equal to today’s dollars. The discounted payback period corrects this by discounting each inflow at the cost of capital before accumulating. Take the same $50,000 investment with $15,000 annual inflows, but now discount at 8 percent, the owner’s borrowing rate.
Discount each year’s $15,000: Year 1: $15,000 / 1.08 = $13,888.89; Year 2: $15,000 / 1.1664 = $12,860.08; Year 3: $15,000 / 1.259712 = $11,907.48; Year 4: $15,000 / 1.360489 = $11,025.45; Year 5: $15,000 / 1.469328 = $10,208.75.
Now accumulate the discounted values: after Year 1, $13,888.89; after Year 2, $26,748.97; after Year 3, $38,656.45; after Year 4, $49,681.90; after Year 5, $59,890.65, which first reaches $50,000. The discounted payback = 4 + ($50,000 – $49,681.90) / $10,208.75 = 4 + ($318.10 / $10,208.75) = 4 + 0.0312 = 4.03 years, or about 4 years and 0.4 months.
Compare: the simple payback was 3.33 years, but the discounted payback is 4.03 years, a full 8 months longer. The 8 percent cost of capital quietly erodes the value of the later inflows, especially Year 4’s $15,000, which is worth only $11,025 in today’s dollars. For projects with paybacks beyond 3 years or discount rates above 5 percent, always compute the discounted version: the simple payback increasingly flatters the project as time and rates grow.
1. Ignoring the time value of money. A 5-year simple payback at a 10 percent cost of capital is far worse than it looks: the later years’ inflows are worth much less than their face value. As the discounted example shows, an 8 percent discount rate stretched a 3.33-year payback to 4.03 years. For any project lasting more than a couple of years, discount the flows or use a metric like NPV that does it automatically.
2. Ignoring cash flows after payback. Project X pays back in 2 years then earns nothing more; Project Y pays back in 4 years then earns $30,000 per year for a decade. Payback ranks X first, but Y creates roughly $250,000 more wealth. Never let a fast payback override total profitability: use payback to filter for risk, then rank the survivors by NPV or IRR.
3. Using payback as the only decision metric. Related to the previous mistake, some businesses approve every project with payback under 3 years and reject everything else. This rule systematically kills valuable long-term investments like research, brand building, and infrastructure, which pay back slowly but create the most value. Payback is a screen, not a verdict.
4. Setting the cutoff arbitrarily. A 3-year cutoff sounds disciplined, but where did it come from? The right cutoff reflects your cost of capital, risk tolerance, and how fast your industry changes. A software company facing rapid obsolescence might rationally demand 2-year payback, while a utility building 30-year infrastructure can accept 8 years. Tie the cutoff to your economics, not to a round number.
5. Mixing nominal and real cash flows. If your inflows grow with inflation at 3 percent per year but you compare the payback against a cutoff derived from today’s dollars, you are mixing units. Keep it consistent: either use nominal (inflation-included) inflows with a nominal cutoff, or strip inflation from both. Inconsistent units quietly shift the answer by months or years on long projects.
Go deeper with the IRR Calculator for the project’s annualized return, the Investment Calculator for growth projections, or browse the full Financial Calculators collection.
This page’s Payback Period Calculator computes the time required for cumulative cash inflows to equal the initial investment. Modes: even annual cash flows or uneven yearly inflows for up to 5 years. Formulas: even flows, payback = initial investment / annual inflow; uneven flows, payback = A + (B / C), where A is full years before recovery, B is the unrecovered amount at the start of the recovery year, and C is the inflow during the recovery year. Reference values: $50,000 investment with $15,000 annual inflow gives 3.33 years (3 years 4 months), with cumulative inflow reaching the investment in year 4. Worked values: $50,000 with uneven flows $10,000, $14,000, $18,000, $20,000, $22,000 gives 3.4 years; discounted at 8 percent, $50,000 with $15,000 annual inflows gives a discounted payback of 4.03 years. Inputs: initial investment in dollars, annual or yearly cash inflows in dollars. Outputs: payback period in years and in years plus months, and the year in which cumulative inflow reaches the investment. Limitations: simple payback ignores the time value of money and all cash flows after payback.
The time needed for an investment’s cash inflows to add up to its initial cost — the break-even point in years.
Divide the investment by the annual inflow ($50,000 ÷ $15,000 = 3.33 years). With uneven flows, add each year’s inflow until you cross the investment.
Shorter is better — many businesses want payback within 3–5 years, but acceptable periods vary by industry and project type.
Payback is simple but ignores the time value of money and all cash flows after payback. Use it alongside NPV or IRR, not instead of them.
Then the inflows are too small — the calculator flags this instead of giving a meaningless number.
Simple payback adds up the raw cash inflows until they cover the investment, ignoring the time value of money. Discounted payback first discounts each inflow at your cost of capital, then accumulates. On a $50,000 investment with $15,000 annual inflows at an 8 percent discount rate, simple payback is 3.33 years but discounted payback is 4.03 years. Discounted payback is always longer and more honest for multi-year projects.
Yes, and that means the project never pays back. If the total of all expected inflows is less than the investment, the cumulative line never crosses the cost and there is no payback period to report. The calculator flags this instead of giving a meaningless number. For example, a $50,000 machine with $8,000 annual inflows over a 5-year life recovers only $40,000, so it never pays back and should be rejected on payback grounds.
For risk and liquidity, yes: faster recovery means less exposure. But payback ignores everything after break-even, so a 2-year payback on a project that then earns nothing is worse than a 5-year payback on a project that then earns millions. Use payback to reject the dangerously slow, then choose among the survivors with NPV or IRR.
Sources: standard corporate finance references, including Brealey, Myers and Allen’s Principles of Corporate Finance and the CFA Institute curriculum.
Also try our IRR Calculator and Investment Calculator — or browse all Financial Calculators.