How to calculate ROI (return on investment)
ROI is the number everyone quotes to justify a decision. Calculated honestly, it tells you whether money spent actually came back with more — and how that option stacks up against others.
Skip the math — the free roi and payback period calculator runs this from your own figures.
Open the free calculator →The basic formula
Return on investment is the net gain from an investment divided by its cost, expressed as a percentage. The formula is: ROI = (total return − cost) ÷ cost × 100.
Example: you spend $10,000 and it generates $15,000 in total. Your net gain is $5,000, so ROI = 5,000 ÷ 10,000 = 50%. Every dollar invested came back as a dollar-fifty.
Always include the full cost
The most common way to inflate ROI is to undercount the cost. Include everything the investment really required — not just the sticker price, but setup, your time, training, and ongoing running costs.
A marketing campaign isn't just the ad spend; it's the design, the tools, and the hours to run it. Leave those out and the ROI looks great while the real return is thinner.
ROI needs a time frame
A 50% ROI over one year is excellent; the same 50% over ten years is mediocre. ROI on its own ignores time, so always state the period it covers — and when comparing options, compare them over the same horizon.
For a fairer comparison across different time spans, people annualize ROI, converting it to an equivalent yearly rate. At minimum, never compare a one-year ROI to a five-year one as if they're the same.
Pair ROI with payback period
ROI tells you how much you get back; payback period tells you how fast. Payback is the time it takes for an investment to earn back its cost — a $10,000 investment returning $2,500 a year pays back in four years.
Read together they're powerful: a high ROI with a slow payback carries more risk than a modest ROI that returns your money quickly. Cautious decision-makers often weigh payback as heavily as ROI.
Turn it into a decision
The point of ROI isn't the number — it's the ranking. Calculate ROI and payback for each option on a level playing field, and the best use of limited money usually becomes obvious.
The free calculator below computes payback, total return, net gain, and ROI for several investments side by side, so you can compare and rank them honestly before committing.
Questions
What is a good ROI?
It depends on the risk and the alternative. As a rough anchor, many small businesses look for investments that clearly beat what the money could earn elsewhere and pay back within a couple of years. A 'good' ROI is one that comfortably exceeds your alternatives for a level of risk you're willing to take — there's no single universal number.
What's the difference between ROI and profit?
Profit is a dollar amount — what you made. ROI is that gain relative to what you spent, as a percentage — how efficiently you made it. A big project can produce a large profit but a poor ROI if it tied up a lot of money, while a small, cheap bet can show a high ROI on modest profit. Look at both.