Calculate distributions fast and easy. Distribution Calculator help you with distribution calculations. The user simply enters the degrees of freedom, the test statistic or the level of signifance, and the program calculates the probability or the test statistic, respectively.
This software offers calculations for the normal distribution, the t distribution, the chi-square distribution, and the F distribution. As can be seen from the screen shot you may select for one-sided or two-sided tests. The probabilities beyond the critical values are colored in red.

The license of this software is Freeware, you can free download and free use this calculator software.