Margin of Error Calculator
Other Survey Tools:
FAQs
What is a margin of error?
The margin of error is a statistic that expresses the amount of random sampling error in a survey’s results. It indicates how much the results might differ from the true population value.
Why is the margin of error important?
It helps you understand the reliability and precision of survey results. A smaller margin of error means more confidence in the results.
Does population size affect the margin of error?
Yes, especially if the sample is a large portion of the population. For smaller populations, a finite population correction factor is applied.
Can I reduce the margin of error?
Yes. You can reduce it by increasing the sample size, decreasing the confidence level, or reducing variability.
What if I don’t know the population size?
If unknown, many calculators assume an infinite population for simplification, which is generally acceptable for large groups.
Is the margin of error the same as confidence level?
No. The margin of error is the range; the confidence level is how sure you are the population value falls within that range.