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

  1. Enter your control group data (original version):
    • Total number of visitors
    • Number of conversions
  2. Enter your variant group data (new version):
    • Total number of visitors
    • Number of conversions
  3. Set your desired significance level (default 95%)
  4. 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

  1. Website Optimization:

    • Landing page changes
    • Call-to-action modifications
    • Design updates
  2. Pricing Tests:

    • Price point optimization
    • Discount strategies
    • Package comparisons
  3. Feature Launches:

    • New feature validation
    • UI/UX improvements
    • Content strategy testing

Best Practices

  1. Sample Size Requirements:

  2. Test Duration:

  3. 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

  1. Plan Ahead:

    • Calculate required sample size before starting
    • Set test duration based on traffic volume
    • Define success metrics in advance
  2. Monitor Health:

    • Check for test validity regularly
    • Look for data collection issues
    • Verify even traffic distribution
  3. 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.