Calculate your Sample Size

Population Size

Confidence Level (%)

Margin of Error (%)

Sample Size


How many people need to take your survey?

Wanna know how to measure it?

Our Sample Size Calculator is here to help. It helps you to find and decide how many people you need to interview to get results that will represent the target population as accurately as possible.

Here's what you need to know about ensuring the survey's correct number of interviews / responses / sample size.

Why sample size?

Surveying a large group of people is not feasible and very expensive. To solve the problem of inferring the whole population we use sampling. The accurate size of sample can be used to represent the whole group.

Key terms:

Population size: Total number of people in the population you are researching. If you survey your organization, population size is the total number of employees.

Confidence level: A percentage that indicates how sure you can be that a certain amount of the population will select a answer. A 95 % confidence level, for example , means that the outcomes between x and y are 95% certain.

Margin of error: A percentage that tells you how much you would expect your survey results to represent overall population views. The lower the margin of error, better the confidence.

Sample Size Formula:

Sample Size Formula