ROI Calculator — return, payback period and annualised rate
Compare investments on return, payback and annualised terms rather than headline percentage alone.
Free and instant — results appear in seconds. No sign-up, no limits, and nothing you type is stored.
Raw ROI is the easiest investment metric to quote and the easiest to mislead with, because it ignores time entirely.
Add the duration and the calculator also returns payback period and annualised ROI, which is the figure that makes investments of different lengths comparable.
Two campaigns, same ROI, different quality
Both return 150% on a 100,000 spend.
Campaign A — over 3 months
Net gain 150,000
ROI 150.00%
Payback period 2.0 months
Annualised ROI 1,462.50%Campaign B — over 24 months
Net gain 150,000
ROI 150.00%
Payback period 16.0 months
Annualised ROI 58.11%
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Identical headline ROI. Campaign A returns capital in two months and can be run again — repeatedly — within the time Campaign B takes to complete once. On an annualised basis it is more than twenty times better.
Quoting the 150% alone treats these as equivalent. They are not remotely equivalent, and the difference is entirely in the time column.
What ROI leaves out
Time, unless you annualise. Two identical percentages over different periods are different investments.
Risk. A guaranteed 20% and a speculative 20% are not the same, and ROI cannot distinguish them.
Opportunity cost. The relevant comparison is against the next best use of the money, not against zero.
Ongoing cost. An investment returning 150% once and one returning 150% annually are described identically by ROI.
Marketing ROI needs attribution
Assigning revenue to a specific campaign is the hard part, and most ROI figures in marketing are attribution assumptions dressed as arithmetic.
Before trusting a campaign ROI, ask what would have happened without it. Customers who would have bought anyway, credited to a retargeting campaign, produce impressive numbers that represent no incremental revenue at all.
Payback period
Often more useful than ROI for operating decisions, because it answers a cash flow question: when does the money come back and become available again. A business with limited working capital should usually prefer a fast payback at moderate return over a slow one at high return.
Frequently asked questions
What is a good ROI?
There is no universal figure — it depends on the risk, the timeframe and what else you could do with the money. A 15% return on a low-risk investment can be excellent while 15% on a speculative one is poor. Compare against your next best alternative, not against zero.
Why does annualised ROI matter?
Because raw ROI ignores time completely. A 150% return over three months and a 150% return over two years look identical as headline figures and are entirely different investments. Annualising puts them on comparable terms.
Should I use ROI or payback period?
Both answer different questions. ROI measures total efficiency; payback period measures how quickly capital becomes available again. If working capital is tight, payback usually matters more, because a fast-returning investment can be repeated while a slow one ties money up.
Why are marketing ROI figures often unreliable?
Because attributing revenue to a specific campaign is a judgement, not a measurement. Customers who would have purchased anyway, credited to a retargeting campaign, produce excellent numbers representing no incremental revenue. Ask what would have happened without the spend.
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