Confidence Interval Calculator
Calculate confidence intervals for means and proportions with detailed statistical analysis. Get margin of error, critical values, and interpretation guides.
Select Calculation Type
Mean Calculation Parameters
Proportion Calculation Parameters
Confidence Interval Results
Detailed Statistics
Interpretation
Calculate a confidence interval to see the interpretation of your results.
How the Confidence Interval Calculator Works
Our confidence interval calculator provides precise statistical analysis for both population means and proportions, automatically selecting the appropriate distribution and providing detailed interpretations.
- Mean Confidence Intervals: Calculate confidence intervals for population means using either Z-distribution (known σ) or t-distribution (unknown σ) based on your data.
- Proportion Confidence Intervals: Calculate confidence intervals for population proportions using the normal approximation with appropriate continuity corrections.
- Comprehensive Results Display: View detailed statistical output including margin of error, critical values, standard error, and confidence interval bounds.
- Multiple Confidence Levels: Choose from standard confidence levels (90%, 95%, 99%) or enter a custom confidence level for specialized analysis.
- Statistical Interpretation: Get clear, educational interpretations of your confidence interval results to understand what they mean in practical terms.
The calculator automatically selects the appropriate statistical distribution and provides accurate critical values for reliable confidence interval estimation.
Common Applications of Confidence Intervals
Scientific Research
Estimate population parameters from sample data in medical studies, psychology research, and scientific experiments.
Business Analytics
Analyze customer satisfaction, market research data, and quality control metrics with statistical confidence.
Quality Control
Monitor manufacturing processes and product quality by establishing confidence intervals for key metrics.
Educational Assessment
Analyze test scores, survey results, and educational research data with proper statistical inference.