Confidence Interval Calculator

Free online confidence interval calculator. Calculate the lower and upper bounds and margin of error for a given sample mean.

Confidence Interval Calculator

Confidence Interval (95%)

Lower Bound

95.8422

Upper Bound

104.1578

We are 95% confident that the true population mean falls within this range.

Margin of Error (E)± 4.1578

What is a Confidence Interval?

A confidence interval displays the probability that a parameter will fall between a pair of values around the mean. It measures the degree of uncertainty or certainty in a sampling method.

Margin of Error

The Margin of Error (MOE) represents the radius of the confidence interval. It is calculated by multiplying the Critical Value (Z-score for normal distribution) by the Standard Error of the sample.

  • Higher Confidence Level: Results in a larger Margin of Error and a wider Confidence Interval.
  • Larger Sample Size (n): Results in a smaller Margin of Error and a narrower Confidence Interval, indicating greater precision.