Free Conversion Probability Calculator
Calculate the probability of hitting your target conversion rate based on current traffic, conversions, and test duration.
How to Use Conversion Probability Calculator?
Enter Your Data
Enter visitors, current CR, target CR, daily traffic, and test duration.
Get Results
Click Calculate to see your probability percentage with confidence level.
Copy Report
Copy the full report to plan your test duration or share with your team.
About Conversion Probability Calculator
Find out the likelihood of reaching your target conversion rate. Enter your current visitors, conversion rates, daily traffic, and test duration to get a probability percentage with confidence level, minimum sample size, and estimated days needed.
How Probability is Calculated
The tool estimates probability using your expected test visitors (daily traffic × test days), the ratio between current and target conversion rates, and realistic constraints. Higher traffic volumes and smaller conversion lifts result in higher probability.
Realistic penalties are applied automatically: targets over 3× your current rate are heavily penalized (80% reduction), targets over 2× get a 50% reduction, and targets over 1.5× get a 25% reduction. Tests with fewer than 1,000 expected visitors are capped at 25% probability and flagged as insufficient data.
