Welcome to the critical value calculator by **ONLINE**! Here you can quickly determine the critical values for most common distributions in statistical testing. In the following, we are focusing on **T distribution**.

Hypothesis test is a method of statistical inference used to decide whether the data at hand sufficiently support a particular hypothesis, namely null hypothesis. **Critical values** allow you to decide whether to **reject** or **non-reject** the null hypothesis. Critical values divide the scale of your test statistic into the rejection region and non-rejection region.

Here are the steps you need to follow:

- Specify the
**degrees of freedom ,n,**of the t distribution. - Set the
**significance level, A**. You can choose the value to your needs. - Set the decimal digit as you require.
- The
**critical value, t**will then be calculated correspondingly._{A,n}

The figure below shows the relationship between the above parameters.

**Example:** Calculate the critical value of T distribution with degree of freedom (n) = 20 and significance level (A) = 0.95. it is shown by t_{20,0.95}. the decimal digit is 4. The following figure shows the value of t distribution.

The t_{20,0.95=1.7247 }displays on output box. The concept of this calculation is shown below.