Hypothesis Test Calculator
Perform one-sample z-test or t-test to test hypotheses about population mean
About this calculator
The Hypothesis Test Calculator performs statistical hypothesis testing to determine whether your sample data provides sufficient evidence to reject or accept a null hypothesis about a population mean. This tool automatically performs one-sample z-tests (when population standard deviation is known) or t-tests (when using sample standard deviation), calculating critical values, p-values, and test statistics. It's essential for researchers, students, and analysts conducting statistical inference to make data-driven decisions with confidence.
How to use
Enter your sample data including sample mean, sample size, and either population or sample standard deviation. Input your null hypothesis value and select your significance level. Choose between one-tailed or two-tailed tests, then click calculate to get your test statistic, p-value, and conclusion.
Frequently asked questions
When should I use a z-test versus a t-test?
Use z-test when population standard deviation is known or sample size ≥30. Use t-test when population standard deviation is unknown and sample size <30.
What's the difference between one-tailed and two-tailed tests?
One-tailed tests check if the mean is significantly greater or less than the null value. Two-tailed tests check if it's significantly different in either direction.
How do I interpret the p-value result?
If p-value < significance level (typically 0.05), reject the null hypothesis. If p-value ≥ significance level, fail to reject the null hypothesis.