How to use the standard error of a proportion calculator
Find the standard error and 95 percent margin of error of a sample proportion. Enter sample proportion, sample size in the fields above; the standard error of proportion, margin of error at 95% are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “standard error proportion”, “margin of error proportion”, “sampling error of percentage”, “calculate standard error of a proportion”, “find standard error of proportion”.
Formula
Variables
- p — Sample proportion
- n — Sample size
Worked example
With sample proportion = 0.3, sample size = 200, the calculator gives standard error of proportion ≈ 0.0324037; margin of error at 95% ≈ 6.351126 %.
Frequently asked questions
What is the standard error of a proportion calculator used for?
Find the standard error and 95 percent margin of error of a sample proportion. It helps with questions such as “standard error proportion”, “margin of error proportion”, “sampling error of percentage”.
What is the formula for the standard error of a proportion calculation?
Standard error of proportion = √(p × (1-p) / n). Margin of error at 95% (%) = 1.96 × [Standard error of proportion] × 100. Here p is sample proportion, n is sample size.
What inputs do I need for the standard error of a proportion calculator?
You need sample proportion, sample size. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the standard error of a proportion calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the standard error of a proportion result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.