Margin of error
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Margin of error3.1 %
Formula
e = z·√(p(1−p)/n)
Worked example
Given: Confidence level = 95%; Sample size = 1,000; Proportion = 50 %
Result: Margin of error = 3.1 %
How it is calculated
1. Enter the values you know. 2. The calculator converts them to base units and applies the formula. 3. The result is shown in the unit you choose.
Frequently asked questions
How do I calculate it?
Formula: e = z·√(p(1−p)/n). Given: Confidence level = 95%; Sample size = 1,000; Proportion = 50 %. Result: Margin of error = 3.1 %.
Is the calculator free and private?
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