This simple online tool allows you to calculate the sampling error for any sample. The DSS tool calculates the finite population correction factor when appropriate to adjust the sampling error upward to account for measuring a significant portion of the population universe. Click here to view more in-depth information which describes Finite Population Correction Factor. To view more information about sampling error, click here.

To calculate the sampling error for a completed project or proposed research project, fill in the appropriate values below.

Sample Size:		Enter the size of the sample drawn from the population being studied.
Sample Proportion (%):		Enter the proportion of people in the population being surveyed who are expected to answer a certain way on the key measure in the survey. If you are unsure what the proportion might be, use 50% because this produces the maximum possible variation.
Total Population:		Enter the total size of the population you are studying. If the total population you are studying is small or your sample makes up at least 5% of the entire population, entering the population here will reduce the sampling error calculated. If you are unsure what amount to put here, leave it blank.
Confidence Interval:	80% 85% 90% 95% 96% 98% 99% 99.9%	Select the desired confidence interval to base the sampling error on. A 95% confidence interval if typical.
Calculate Sampling Error		Sampling Error »