Marketing ROI Calculator
This marketing ROI calculator helps teams estimate the return from a campaign. Enter spend, monthly leads, lead-to-customer conversion rate, and average deal value to see modelled ROI, customers, revenue, profit, cost per lead, and cost per acquisition.
What this tool measures
Marketing ROI compares what a campaign returned with what it cost. This calculator turns four numbers you already track, monthly spend, leads, lead-to-customer rate and average deal value, into customers won, revenue, profit, return on investment, cost per lead and cost per customer.
It is built for the quick sanity check that happens before a budget meeting: is a channel paying for itself at current conversion rates, and which input would have to move for it to do so?
How to read each field
- Monthly Marketing Spend
- Everything you paid for the channel or campaign in the month: media spend plus any agency, tool or freelancer cost attributable to it. Leaving out fees makes the result look better than it is.
- Leads Generated / Month
- Enquiries that reached you from that spend, counted the same way each month (form fills, calls you logged, chats you qualified).
- Lead-to-Customer Rate
- The share of those leads that became paying customers, as a percentage. Use your own close rate from the CRM; a guess here drives the whole result.
- Average Deal Value
- Revenue per customer won. For repeat or subscription businesses decide whether to use first-order value or a longer-run figure, and keep that choice consistent when you compare channels.
- ROI %, Cost per Lead, Cost per Customer
- ROI is profit divided by spend, shown as a percentage. Cost per lead is spend divided by leads. Cost per customer is spend divided by customers won. Revenue and profit are shown beside them so the percentage can be checked.
Worked example
A service business spends 5,000 in a month and records 100 leads. It closes 10% of them, so 10 customers, and the average deal is worth 1,200. Revenue is 12,000, profit after the 5,000 spend is 7,000, and ROI is 7,000 divided by 5,000, which is 140%. Cost per lead is 50 and cost per customer is 500.
Now change one input. If the close rate falls to 5%, customers drop to 5, revenue to 6,000 and ROI to 20%, while cost per lead stays at 50. The lead price did not change but the channel became far less attractive, which is why cost per lead alone is a poor measure of performance.
Limits to keep in mind
- Profit here means revenue minus marketing spend. It does not subtract the cost of delivering the product or service, so treat it as a ceiling, not net profit.
- The calculator uses one month and one deal value. It does not model sales cycles longer than a month, repeat purchases or attribution between channels.
- Results are only as good as the inputs. Use your own tracked numbers and revisit them each quarter.
Frequently asked questions
What is a good marketing ROI?
There is no universal figure. It depends on your margins, sales cycle and how long customers stay. A business with thin margins needs a higher ROI than one with high margins. Compare channels against each other and against your own break-even point rather than against a headline benchmark.
Should I include agency fees in monthly spend?
Yes. If you count only ad spend, the ROI looks better than the real return. Include any fee, tool or production cost that exists to run the channel.
Why does ROI fall when cost per lead stays the same?
Because ROI depends on how many leads turn into customers and what each customer is worth. A lower close rate or smaller deal value reduces revenue even if each lead costs the same to get.
Terms explained
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