Critical Values Calculator – Fast & Accurate

This tool helps you find critical values for your statistical calculations easily and quickly.

Critical Values Calculator

This calculator helps you determine the confidence interval for a given sample’s mean, standard deviation, size, and desired confidence level. Follow the steps below to use it:

How to Use

  1. Enter the sample’s mean (μ).
  2. Enter the sample’s standard deviation (σ).
  3. Enter the sample size (n).
  4. Enter the desired confidence level. Common levels include 80%, 85%, 90%, 95%, and 99%.
  5. Click the “Calculate” button to get the confidence interval.

How It Calculates

The calculator uses the z-score associated with the chosen confidence level to compute the margin of error. It then adds and subtracts this margin of error to/from the mean to get the lower and upper bounds of the confidence interval.


This calculator assumes a normal distribution and uses z-scores. For larger sample sizes, a t-distribution might be more appropriate. Also, accuracy depends on the precision of the input values.

Use Cases for This Calculator

Calculate Critical Value for Z-distribution

Need to find the critical value for a Z-distribution? Simply enter the confidence level and let the calculator do the rest, giving you the critical value you need for your statistical analysis.

Calculate Critical Value for T-distribution

For T-distributions, you can easily determine the critical value by inputting the degrees of freedom and the confidence level. Instantly get the critical value required for your study or research.

Calculate Critical Value for Chi-square Distribution

Working with Chi-square distributions? Enter the degree of freedom and significance level to quickly obtain the critical value, facilitating your calculations for goodness-of-fit tests and more.

Calculate Critical Value for F-distribution

Handling F-distributions? Input the degrees of freedom for the numerator and denominator, along with the confidence level. Obtain the critical value promptly, aiding you in your ANOVA and regression analyses.

Custom Confidence Level Calculation

If you have a specific confidence level in mind, you can calculate the critical value directly for various distributions by entering the required parameters accurately, ensuring flexibility in your statistical work.

Fast Critical Value Comparison

Quickly compare critical values for different distributions by using the calculator for multiple scenarios. This allows you to make efficient decisions based on varying levels of significance and confidence.

Real-time Critical Value Updates

See critical value changes in real-time as you tweak the input parameters, providing immediate feedback on how adjustments impact the required critical values for your statistical tests or experiments.

Clear Output Presentation

Receive the critical value output in a clear and concise format, making it easy to interpret and apply the results to your statistical hypothesis testing, ensuring accuracy and efficiency in your analysis.

Accessible Calculation for Researchers

Make critical value calculations accessible to researchers of all levels by offering a user-friendly interface that simplifies the process. Enhance the research experience by providing a valuable tool for statistical analysis.

Interactive Learning Tool

Engage in interactive learning by using the critical value calculator to understand the concept of significance levels and critical values better. Experiment with different inputs to grasp the importance of these values in statistical analysis.

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