The Sampling Error Calculator estimates how much a sample’s mean is expected to differ from the population mean purely due to random variation. By entering the sample’s standard deviation and size, the calculator applies the formula SE=snSE = \frac{s}{\sqrt{n}}SE=n​s​ to measure this expected deviation. A smaller sampling error indicates that the sample mean is a more accurate estimate of the population mean, which is crucial in surveys, research studies, and data analysis to evaluate the reliability of sampled data.