Free Calculator
Margin of Error Calculator
Calculate the margin of error for survey results given your sample size, confidence level, and observed proportion.
Survey Parameters
The percentage in your survey who answered "yes" or selected the option.
50%
Apply finite population correction for small populations.
Margin of Error
±5.00%
At 95% confidence
Confidence Interval
45.0% – 55.0%
True value is within this range 95% of the time
Interval visualisation
0%50% ± 5.00%100%
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Read our full guide on statistical concepts, covering study design, interpretation, and common mistakes.
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