Definition
ROI (Return on Investment) is the net return on an investment divided by the investment's cost: (return − cost) / cost, expressed as a percentage.
Also called: ROI, Return on Investment, Return on investmentCompare net return with the investment.
Change the inputs to see how numerator and denominator affect the result.
ROI vs. ROAS
Where ROAS looks only at ad revenue per ad euro, ROI can hold the entire effort: ads, tools, hours, agency, and measures against the net return, not the revenue. Invest €13k and get €30k in contribution margin back, and ROI is 130% ((30,000 − 13,000) / 13,000).
That makes ROI a broader, more honest business goal than ROAS — but also a less precise one, because it depends on what you count in both the numerator and the denominator. Be consistent, or the number can mean anything.
When ROI is the right measure
ROI is strongest for assessing a whole investment — a campaign, a tool, a hire — over a period where you can total up both cost and return. For day-to-day bid management, POAS and contribution margin are more operational, because they work at the order and product level.
Calculate ROI on profit (contribution margin), not revenue. Revenue ROI overstates the return just as much as revenue ROAS does, and leads to the same wrong decisions.
Frequently asked questions
What's the difference between ROI and ROAS?
ROAS measures revenue per ad euro and looks only at ads. ROI measures net return against the total investment and can include all costs. ROI is a broader business goal; ROAS is a narrower channel metric.
Should ROI be calculated on revenue or profit?
On profit (contribution margin). Revenue ROI ignores margin and costs and overstates the return — exactly the trap POAS fixes relative to ROAS.
From insight to action
See how it applies in practice.
Growth also needed a better purchasing process
We built Matraws' trade-in system with submission, assessment, offers and handling in one backend. The work addressed supply as a constraint.
Read the casePriorities and collaboration
Discuss your next step
Tell us where your business stands. We clarify the work needed and whether we are the right fit.
Choose a time30 minutes · No obligation
About the author
Nicklas Segatz Mortensen
Growth hacker and fractional CMO with 10+ years' experience and hundreds of millions in managed ad spend behind him. Background from larger Danish and international scale-ups, and from the agency world.
Meet the team