Formulas used by this calculator
- Conversion rate (%) = conversions or conversion credit ÷ eligible interactions × 100
- Use the denominator and conversion action belonging to the same report
Worked example
An illustrative campaign has 35 conversions from 1,000 eligible interactions. Its conversion rate is 35 ÷ 1,000 × 100 = 3.5%.
If attributed conversion credit is 34.5 instead, the rate is 3.45%. Fractional credit is allowed; it does not mean half a physical customer exists.
Name the conversion before measuring it
Google Ads defines conversion rate against eligible interactions and explains why attribution can produce fractional conversion credit. Google Ads: interpreting conversion data.
Choose one outcome such as a completed purchase, a qualified lead, or an appointment. Combining a form submission and its resulting sale into one numerator can count two steps of the same journey. A higher combined total would not mean more customers.
Choose a denominator that answers the question
Use sessions when the question is about outcomes per visit, users when it is about outcomes per person under a matching definition, and eligible ad interactions when reconciling that platform metric. The form deliberately names the denominator instead of assuming every report means clicks.
Do not use all website traffic beneath conversions from a single paid campaign. Likewise, avoid putting view-attributed outcomes above an unrelated click-only denominator. Write the report's scope beside the worksheet so another reader can reproduce the calculation.
Separate a rate change from a tracking change
If the number moves sharply, inspect both counts. A new conversion event, different counting rule, or incomplete recent period can change the ratio without changing customer behavior. Compare data with the same maturity and measurement definition.
The calculator returns a descriptive rate, not a causal effect or statistical significance result. Use the rate to locate a question worth investigating. Then inspect the journey, outcome quality, and relevant experiment before changing the budget.
Common questions
Can conversion rate exceed 100%?
An event-based report can count several conversions per eligible interaction. That ratio can exceed 100%, but it is not a unique-visitor conversion probability. The tool flags this distinction instead of silently capping the result.
Why does zero traffic show an undefined rate?
There is no denominator from which to measure a rate. Positive traffic with zero conversions gives 0%; zero traffic gives an undefined result even if conversion credit has been entered.