Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

Margin of Error Calculator

Find the margin of error for a survey proportion at a chosen confidence level. Tells you how far a poll result might be from the true population value.

Sample Size (people)

Sample Proportion (%)

Z-Score (1.96 = 95%)

Probability

Confidence Interval Calculator

Computes the range of values likely to contain a true population mean at your chosen confidence level. Use it when reporting survey results, clinical trial outcomes, or any estimate derived from a sample.

Sample Mean

Sample Standard Deviation

Sample Size (n) (observations)

Confidence Level

Distribution Type

Key differences

	Margin of Error Calculator	Confidence Interval Calculator
Category	Statistics	Probability
Inputs required	3	5
Result	Margin of Error (%)	Margin of Error (±)
What it does	Find the margin of error for a survey proportion at a chosen confidence level. Tells you how far a poll result might be from the true population value.	Computes the range of values likely to contain a true population mean at your chosen confidence level. Use it when reporting survey results, clinical trial outcomes, or any estimate derived from a sample.