Calculate the required sample size for a given margin of error and confidence level. This calculator helps determine how many observations are needed for reliable statistical inference.
Calculate the required sample size for a given margin of error and confidence level. This calculator helps determine how many observations are needed for reliable statistical inference.
Enter the population standard deviation (estimated)
Enter the desired margin of error
The required sample size is the square of the product of the critical z-value and standard deviation, divided by the desired margin of error.
How this calculator works
The required sample size is the square of the product of the critical z-value and standard deviation, divided by the desired margin of error.
Common questions about this calculator
