P-value Calculator
Please provide any one value below to compute p-value from z-score or vice versa for a normal distribution.
A p‑value, short for probability value, serves as a gauge in statistical hypothesis testing to assess whether the results obtained are unlikely to have occurred by chance. In such testing, the null hypothesis represents the default assumption – for instance, that no link exists between groups or variables. If we accept the null hypothesis as true, the p‑value expresses the chance of witnessing test outcomes at least as extreme as those observed. Thus, calculating a p‑value indicates how probable it is that the observed data truly diverge from the null hypothesis.
When the p‑value is small, the result is deemed more significant, providing stronger grounds to discard the null hypothesis in favor of an alternative. Conventionally, a p‑value of ≤ 0.05 is treated as a sign of significance, leading to rejection of the null hypothesis, whereas a p‑value above 0.05 suggests insufficient evidence to do so.
Given that the data being studied follows a normal distribution, a Z-score table can be used to determine p-values, as in this calculator.