The Sample Size Calculator helps determine how many observations are required to accurately estimate a population parameter within a desired confidence level and margin of error. It uses the formula n=(Z×σE)2n = \left(\frac{Z \times \sigma}{E}\right)^2n=(EZ×σ​)2, where ZZZ represents the z-score corresponding to the selected confidence level, σ\sigmaσ is the population standard deviation, and EEE is the allowable margin of error. This tool is essential in research and statistics to ensure that collected data provides reliable and precise results without unnecessary oversampling.