🧮 Sample Size Calculator

Determine the optimal sample size for your survey or experiment

How to Use

  1. Select your desired confidence level (typically 95%)
  2. Enter your acceptable margin of error (typically 5%)
  3. Optionally enter your population size (leave empty for infinite population)
  4. Click "Calculate Sample Size" to get your result

Understanding the Parameters

Confidence Level: The probability that your sample accurately reflects the population. A 95% confidence level means you can be 95% certain your results are within the margin of error.

Margin of Error: The range within which the true population value lies. A 5% margin of error means the true value is within ±5% of your measured value.

Population Size: The total number of people in the group you want to study. If your population is very large (>100,000) or unknown, leave this field empty for infinite population calculation.

💡 Pro Tip

A larger sample size gives more accurate results but costs more to collect. Balance accuracy needs with available resources. For most surveys, 95% confidence with 5% margin of error is a good standard.