Payback Period Calculator
Payback period answers the simplest investment question: how long until I get my money back? Enter the upfront cost and the periodic cash inflow it generates.
How to use this calculator
- Enter the upfront investment.
- Enter the cash inflow it generates and whether that's monthly or annual.
- Press Calculate — then sanity-check big decisions with NPV and IRR too.
Formula used
Assumes roughly constant inflows. For uneven flows, accumulate year by year until the running total crosses the investment. Discounted payback (using present values) runs longer and is more honest for multi-year horizons.
Example calculation
A machine costing 500,000 generating 45,000/month: payback = 11.1 months.
Equivalently, it returns 108% of its cost per year — a very fast payback by most capital-budgeting standards.
Payback's virtue and blind spots
Payback period is beloved for what it really measures: risk exposure time. The longer your money is out, the more can go wrong — so "14 months" communicates risk in a way percentage returns don't, which is why operators screen projects with it and why energy-efficiency and equipment sales lead with it.
Its two blind spots are famous: it ignores everything after break-even (a project paying back in 2 years then dying loses to one paying back in 3 then earning for a decade) and it ignores the time value of money. Screen with payback; decide with NPV and IRR.
Why use this calculator?
- Express an investment's risk as time — the unit intuition understands.
- Compare equipment, marketing and tooling decisions on recovery speed.
- Get the implied simple annual return as a cross-check.
Frequently asked questions
What is a good payback period?
Context rules: under 12 months is excellent for most business equipment and marketing investments; 2–4 years is common for machinery; solar installations often accept 5–8 years for their long asset life. Shorter always means less risk exposure.
What if my cash flows aren't constant?
Accumulate them period by period until the running total covers the investment, interpolating within the crossing period. The NPV calculator on this site accepts uneven flows if you want the discounted view.
Payback vs ROI — what's the difference?
Payback measures time to recover; ROI measures total percentage gain. They can rank projects oppositely: a slow project can have a huge lifetime ROI. Use payback for risk, ROI/NPV for value.