Student's T Distribution Calculator - CDF 2 Tails

Calculates the Student's T distribution cumulative distribution function for 2 tails.

 

See the Statistical Distributions Overview page for more statistical distribution calculators.

Example 1

What is the 2 tail probability associated with a Student’s T distribution with 10 degrees of freedom with a t-value of 1.812?

Value	Keystrokes	Display	Description
10	df	10.00	Stores the df value.
1.812	x	1.812	Stores the x value.
	tdist	0.8999	Calculates the T distribution.

Example 2, Inverse

A hypothesis test requires a critical t-value from the Student's T-Distribution with 25 degrees of freedom. Find the t-value for a 2 tail probability of 0.95

Value	Keystrokes	Display	Description
25	df	25.00	Stores the df value.
.95	tdist	0.95	Stores the tdist.
	x	2.060	Calculates the x value.

Reference:

Student's t-distribution - Wikipedia