Population & sample, with steps — based on current UAE rules. Adjust the inputs and press Calculate.
Fill in the form and press Calculate to see your result here.
Standard deviation measures how spread out a set of numbers is from their mean (average). A low standard deviation means values cluster close to the mean; a high one means they're spread widely.
Use population when your numbers are the entire group you care about. Use sample (dividing by n−1) when your numbers are a sample drawn from a larger population — this is the more common case in surveys and experiments.
Variance is in squared units because it comes from squared differences. Standard deviation converts it back to the original units by taking the square root, which is why it's usually more intuitive to interpret.