Calculator tool
How this calculator works
Use the explanation to understand the formula, assumptions, and practical limits behind the calculator result.
The Core Formula
The tool also shows conversions per 1,000 visitors so the rate is easier to picture at scale.
Define the Funnel First
A conversion can mean a purchase, signup, lead, booking, or another event. The numerator and denominator must describe the same funnel step, otherwise the rate is hard to interpret.
Why Sample Size Matters
Small traffic samples can swing sharply from a few extra conversions. Compare rates only after checking visitor volume, tracking quality, and whether the periods are genuinely comparable.
When Conversions Can Exceed Visitors
If you count events rather than unique people, one visitor may convert more than once. The current calculator warns when conversions exceed visitors so you can confirm that both inputs use the same unit.
Frequently asked questions
What should count as a conversion?
Use the event tied to the decision you care about, such as purchase, lead, signup, or booking. Keep the definition unchanged when comparing periods.
Why compare conversions per 1,000 visitors too?
It turns a small percentage into a more tangible count. A 2.4% rate means about 24 conversions per 1,000 visitors.
Can conversions be greater than visitors?
They can if you count repeat events, but then the metric is no longer a person-level conversion rate. The warning exists so you verify that the numerator and denominator match.
How much should I trust a rate from a small sample?
Use caution. Small samples are noisy, and a few events can move the percentage sharply. Check volume before declaring one funnel better than another.
