Confidence Interval Calculator
Calculate the confidence interval for a population mean or proportion. Used in hypothesis testing and survey analysis.
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What this calculator does
Confidence Interval Calculator helps you quickly estimate calculate the confidence interval for a population mean or proportion. used in hypothesis testing and survey analysis. with clean output and clear next steps.
How the calculation works
Enter Sample Mean (x̄), Standard Deviation (σ or s), Sample Size (n) and this calculator uses standard formulas to determine Lower Bound and Upper Bound. The output is displayed immediately in a user-friendly format.
Example calculation
For example, enter realistic values into the Confidence Interval Calculator to see how the calculator produces Lower Bound and Upper Bound that you can use for planning and comparison.
Disclaimer
The calculations provided by this website are for informational purposes only and should not be considered financial, legal, tax, or professional advice.
Frequently Asked Questions
What does a 95% confidence interval mean?
It means 95% of similarly constructed intervals would contain the true population parameter. It does NOT mean a 95% chance the parameter is in this specific interval.