Two Sample T-Test Calculator

Summary

Enter data for two groups to compute the t-statistic, p-value, and determine if the difference in means is statistically significant.

How it works

1. Enter the data values for Group 1, one number per line or comma-separated.
2. Enter the data values for Group 2 in the same format.
3. Select your desired significance level (alpha) — commonly 0.05.
4. Click "Run T-Test" to compute the t-statistic, degrees of freedom, and two-tailed p-value.
5. The result shows whether to reject the null hypothesis at your chosen alpha.
6. Descriptive statistics (mean, variance, standard deviation) for each group are also displayed.

Use cases

• Compare test scores between two classroom groups to check if a teaching method made a difference.
• Evaluate whether a new drug produces a significantly different outcome than a placebo.
• Determine if conversion rates differ between two A/B test variants.
• Assess whether salary data differs between two departments.
• Validate experiment results in scientific research and data analysis.
• Check if a product change measurably improves or harms a key metric.

Frequently Asked Questions