This free ROI calculator measures marketing campaign profitability by comparing revenue generated against costs invested. Enter your budget, cost per lead, conversion rate, and average sale value to instantly calculate return on investment, total leads, sales, and revenue. ROI above 100% means your campaign generates more revenue than it costs—essential data for marketing budget decisions.
Key Takeaways
- ROI formula: ((Revenue – Cost) / Cost) × 100 = ROI percentage
- Benchmark: Marketing campaigns typically target 300-500% ROI minimum
- Key inputs: Budget, cost per lead, lead-to-sale conversion rate, average sale value
- Decision driver: ROI data determines which campaigns to scale and which to cut
How to Calculate Marketing ROI
Marketing ROI measures the return generated for every pound invested in a campaign. The formula is straightforward: subtract your cost from revenue, divide by cost, then multiply by 100 for a percentage.
Formula: ROI = ((Revenue – Cost) / Cost) × 100
Example: A £1,000 campaign generating £4,000 revenue produces 300% ROI. For every £1 spent, you received £3 in profit plus your original £1 back.
Understanding the Calculator Inputs
Budget
Your total campaign spend including ad costs, creative production, and management fees. Include all costs attributable to the campaign for accurate ROI calculation.
Cost Per Lead (CPL)
How much you spend to acquire each lead. Divide total campaign cost by number of leads generated. Lower CPL increases ROI if conversion rates remain constant.
Lead to Sale Conversion Rate
The percentage of leads that become paying customers. A 10% conversion rate means 10 out of every 100 leads purchase. Improving conversion rate directly increases ROI without additional ad spend.
Average Value Per Sale
Revenue generated per customer transaction. Include initial purchase only, or factor in customer lifetime value for long-term ROI analysis.
What Is a Good Marketing ROI?
Most businesses target 300-500% ROI as a baseline for sustainable marketing. This means generating £3-5 for every £1 spent. However, acceptable ROI varies by industry, sales cycle length, and customer lifetime value.
High-ticket B2B services may accept lower initial ROI knowing customer relationships span years. E-commerce with thin margins requires higher immediate ROI to remain profitable.
How to Use This Calculator
- Enter your total campaign budget
- Input your cost per lead (or estimate from similar campaigns)
- Enter your lead-to-sale conversion rate as a percentage
- Input your average sale value
- Review calculated ROI, total leads, sales, and revenue
Use the calculator to model scenarios before launching campaigns. Adjust inputs to find the metrics needed for target ROI.
Free tool by: John Isaacson, Digital Marketing Strategist
Last Updated: January 2026
