T-Test Calculator
Perform a one-sample or two-sample (Welch's) t-test using summary statistics. Enter the sample mean, standard deviation, and size to calculate the t-statistic and p-value.
The t-test determines whether the means of groups are statistically different.
One-Sample T-Test: t = (x̄ - μ₀) / (s / √n)
Two-Sample T-Test (Welch's): t = (x̄₁ - x̄₂) / √(s₁²/n₁ + s₂²/n₂)
Welch's t-test does not assume equal variances and uses the Welch-Satterthwaite equation for degrees of freedom.