Set Your Precision
Choose your confidence level and margin of error to define how precise your results need to be.
Study Parameters
Cross-sectional household or beneficiary survey
Total number of individuals in the target population. Leave blank if unknown or very large.
Higher confidence requires a larger sample size
%
±1% (very precise)±10% (rough estimate)
Smaller margins of error require larger samples (range: 1%-10%)
Required Sample Size
385
respondents
Confidence Level
95%
Z = 1.96
Margin of Error
±5%
precision
Population
∞
infinite (assumed)
Methodology
This calculator uses the Cochran formula with maximum variability (p = 0.5) for the most conservative estimate. The formula is: n = (Z² × p × (1-p)) / MoE².
How It Works
This calculator uses the Cochran formula, a widely accepted method for determining minimum sample sizes in survey and evaluation research.
Cochran Formula
The calculator applies n = (Z² x p x (1-p)) / MoE² with maximum variability (p = 0.5) for the most conservative estimate.
Finite Population Correction
If your population is known and limited, the formula applies a finite population correction to reduce the required sample size.
Need Help With Your Survey Design?
Our M&E consultants can help you design statistically sound sampling strategies, navigate complex cluster designs, and ensure your evaluation meets rigorous standards.