Hong Life CalculatorsUnderstanding the marketing ROI calculator — concept and principle
Marketing ROI (return on investment) measures how much profit a campaign generated for each unit of money spent on it. Unlike ROAS, which divides revenue by ad spend, marketing ROI subtracts the cost of the goods sold and the marketing cost itself, so it tells you whether the campaign actually made money. Use it to evaluate a finished campaign, compare channels or set a budget ceiling. It works with any currency.
How it is calculated
- Gross profit = revenue attributed − cost of goods sold
- Net profit after marketing = gross profit − marketing cost
- Marketing ROI % = (revenue − COGS − marketing cost) ÷ marketing cost × 100
Revenue attributed is the sales you credit to the campaign. Cost of goods sold is the direct cost of the products in those sales. Marketing cost should include media, creative, agency and tool costs for the campaign.
The principle
ROI is the general investment formula, gain minus cost divided by cost. For marketing, the gain is not the revenue but the gross profit those sales create, because the products themselves cost money. An ROI of 0% means the campaign exactly paid for itself; a negative ROI means it lost money even if revenue looks large. The link to ROAS is simple: ROI = ROAS × gross margin − 1, so break-even ROAS = 1 ÷ gross margin.
Worked example
- Revenue attributed $20,000, cost of goods sold $8,000, marketing cost $5,000.
- Gross profit = 20,000 − 8,000 = $12,000.00.
- Net profit after marketing = 12,000 − 5,000 = $7,000.00.
- Marketing ROI = 7,000 ÷ 5,000 × 100 = 140%.
Here ROAS is 4×, and with a 60% gross margin, 4 × 0.6 − 1 = 1.4, the same 140%.
How to read the result
Positive ROI means the campaign added profit before overheads; 140% means each $1 of marketing returned $1 of cost plus $1.40 of profit. There is no universal good level, because ROI depends on margin, how revenue is attributed and the time window. Compare campaigns measured the same way. Note that ROI here is before fixed overheads such as salaries and rent, so a modestly positive ROI may still not cover them.
Common mistakes
- Using revenue instead of gross profit, which is really ROAS.
- Crediting sales that would have happened anyway to the campaign.
- Ignoring repeat purchases that come after the measurement window.
- Leaving out creative and agency costs from marketing cost.
Frequently asked questions
What is the difference between ROI and ROAS?
ROAS = revenue ÷ ad spend; ROI subtracts product and marketing costs and measures profit relative to marketing cost.
What ROI means break-even?
0%. Any value above zero means the campaign earned more gross profit than it cost.
Should I include customer lifetime value?
For subscription or repeat-purchase businesses, an ROI based on lifetime gross profit gives a fairer view, but keep it separate from short-term ROI.
Sources: Farris, Bendle, Pfeifer & Reibstein, Marketing Metrics (Pearson)