The p-Values Calculator is a new Minerazzi tool that is available now at
Submitting a Student’s t value and degrees of freedom returns a p-value. This is a great tool for Student’s t hypothesis testing.
The tool works by numerically approximating the CDF (Cumulative Distribution Function). This is the integral of the PDF (Probability Distribution Function) of the Student’s t Distribution. The theory behind these calculations along with valuable references are given in the tool’s page.
The reverse process, computing t from a p-value is possible by inverting the CDF to compute the Quantile Function (QF), also known as the inverse CDF. Our (soon to be released) t-p Transformations tool computes both the CDF (t-to-p) and QF (p-to-t).