A/B Test Analysis Calculator
Analyze A/B test results with statistical significance testing and confidence intervals
Not Statistically Significant
The difference between variants is not statistically significant.
Conversion Rate Comparison
Significance Distribution
Conversion Rates
Control (A)10.00%
Variant (B)12.00%
Improvement
Absolute2.00%
Relative20.00%
Statistical Details
P-value0.1527
Z-score1.4300
SE of Difference0.0140
Confidence Interval
Lower Bound-0.74%
Upper Bound4.74%
Control Group (A)
Variant Group (B)
How It Works
- Enter your control group data (original version):
- Total number of visitors
- Number of conversions
- Enter your variant group data (new version):
- Total number of visitors
- Number of conversions
- Set your desired significance level (default 95%)
- Get comprehensive statistical analysis of your test results
Understanding the Results
The calculator provides:
- Statistical significance indicator
- Conversion rates for both variants
- Absolute and relative improvement
- P-value and Z-score
- Confidence intervals
Statistical Parameters
- Statistical Significance: Determined by comparing p-value to significance level
- P-value: Probability of seeing such results by chance
- Z-score: Number of standard deviations from the mean
- Standard Error: Expected variation in the difference between conversion rates
- Confidence Interval: Range where the true difference likely lies
Common Use Cases
-
Website Optimization:
- Landing page changes
- Call-to-action modifications
- Design updates
-
Pricing Tests:
- Price point optimization
- Discount strategies
- Package comparisons
-
Feature Launches:
- New feature validation
- UI/UX improvements
- Content strategy testing
Best Practices
-
Sample Size Requirements:
- Ensure sufficient sample size before analysis
- Use our A/B Test Sample Size Calculator
- Don't stop tests early based on preliminary results
-
Test Duration:
- Run tests for complete business cycles
- Account for weekday/weekend variations
- Use our A/B Test Duration Calculator
-
Result Interpretation:
- Consider practical significance alongside statistical significance
- Look at both relative and absolute improvements
- Account for confidence intervals in decision making
Limitations
- Assumes normal distribution
- Best for binary outcomes (conversion/no-conversion)
- Doesn't account for seasonal variations
- Single metric analysis only
Tips for Success
-
Plan Ahead:
- Calculate required sample size before starting
- Set test duration based on traffic volume
- Define success metrics in advance
-
Monitor Health:
- Check for test validity regularly
- Look for data collection issues
- Verify even traffic distribution
-
Make Decisions:
- Consider business impact alongside statistics
- Document learnings for future tests
- Plan follow-up experiments
Related Calculators
A/B Test Sample Size Calculator
Before running your test, use this calculator to determine how many visitors you need for statistically significant results.
A/B Test Duration Calculator
Calculate how long you need to run your test to reach the required sample size based on your daily traffic.