Advanced Sample Size Calculator
How to Use:
- Select your desired Confidence Level. This reflects how sure you want to be that the true population parameter falls within your margin of error.
- Enter the Margin of Error (E) as a decimal (e.g., 0.05 for 5%). This is the acceptable amount of error in your estimate.
- Enter the Estimated Population Proportion (p) as a decimal (e.g., 0.5 if unknown, which maximizes sample size). This is your best guess of the proportion in the population.
- Optionally, enter the Population Size (N) if it's known and relatively small. This allows for a finite population correction. Leave blank if the population is very large or unknown.
- Click "Calculate Sample Size".
- The required sample size will be displayed. Click "Show Details" for formulas, theory, and step-by-step calculations.
Enter as a decimal (e.g., 0.03 for 3%)
Enter as a decimal (0-1). Use 0.5 if unsure.
For finite population correction.