T-Test Sample Size Calculator

T-Test Sample Size Calculator
Calculate sample sizes for independent, paired, and one-sample t-tests with power analysis
Independent Samples T-Test
Compare means of two independent groups
Statistical Parameters
Configure significance level, power, and other study parameters

Type I error rate - probability of false positive (typically 5%)

💡 Example: 5 for p < 0.05 (standard)

Probability of detecting a true effect (80-90% recommended)

💡 Example: 80 for 80% power (standard)