What is Sample Size Calculation?

Sample size calculation determines the number of items to inspect to ensure accurate results. It is based on the Z-score (confidence level), estimated proportion of defects, and margin of error.

How to Use the Calculator

Follow these steps to calculate the sample size:

1. Enter Z-Score: Input the Z-score based on the desired confidence level (e.g., 1.96 for 95% confidence).
2. Enter Estimated Proportion of Defects (p): Input the estimated proportion of defects (between 0 and 1).
3. Enter Margin of Error (E): Input the acceptable margin of error (between 0 and 1).
4. Calculate: Click "Calculate Sample Size" to see the required sample size.

Why is Sample Size Important?

Calculating the correct sample size is essential for:

• Quality Control: Ensuring inspections are statistically valid.
• Cost Efficiency: Avoiding over-inspection or under-inspection.
• Decision-Making: Providing reliable data for process improvement.