Sample Size Calculator
Quickly estimate the minimum sample size needed for a survey, based on confidence level, margin of error, and expected proportion.
1. Enter your assumptions
Total eligible audience (e.g., all customers). If unknown or very large, leave blank.
95% is standard for most brand & customer studies.
Best guess of % answering “Yes / Top 2 box / Aware”. Use 50% if unsure (worst case).
Target precision of your estimate, e.g., ±5 percentage points.