SmartFormBoard
Features
Use Cases
Pricing
Guides
Start Free Trial
Open main menu
Features
Use Cases
Pricing
Guides
Facilitator Tool
Sample Size Calculator
Determine how many responses you need for statistical significance.
JavaScript is disabled.
Standard rule of thumb: ~385 responses are needed for a 95% confidence level with a 5% margin of error on a large population.
Population Size (Total Audience)
Confidence Level
90% (Z-score 1.645)
95% (Z-score 1.96)
99% (Z-score 2.576)
Margin of Error (e.g., 5% = 0.05)
1%
5%
10%
Required Sample Size
385