The Confidence Interval Calculator helps you quickly determine the range within which a population parameter is likely to fall, based on your sample data. You can calculate confidence intervals for both means and proportions using built-in Z and T methods, depending on whether the population standard deviation is known. Simply enter your sample mean, standard deviation (or standard error), sample size, and desired confidence level (90%, 95%, or 99%) to get instant, accurate results. This calculator is ideal for students, researchers, and professionals who need to perform statistical analysis easily and efficiently. It’s fully responsive and can be used as a standalone HTML file or embedded directly into a WordPress site using a Custom HTML block.