Confidence Interval for Proportions
Calculate the confidence interval (CI) of a proportion with the given inputs of sample size, frequency and chosen confidence level.
Code to add this calci to your website
Confidence Interval = p ± Zα/2 × √[(p×q)/n] , (x, n-x≥5)
p = x/n
q = 1-p
α = 1 - (Confidence Level/100)
x = Frequency
n = Sample Size
Zα/2 = Z-table value
Online calculation of Population Confidence Interval (CI) for Proportions is made easier.