Cronbach's Alpha Calculator

Q: How do you calculate Cronbach's Alpha?

Cronbach's Alpha is calculated using the formula: α = (N / (N - 1)) * (1 - (Σσᵢ² / σᵗ²)), where N is the number of items, σᵢ² is the variance of each item, and σᵗ² is the total variance of all items.

This calculator is designed for researchers and statisticians seeking to assess the reliability of psychometric tests or questionnaires. By inputting your data, you can quickly determine the Cronbach's Alpha coefficient, which measures internal consistency.

Calculator

Number of Items *

Item Variances *

Total Variance *

Results

Cronbach's Alpha 0.00

Data Source and Methodology

All calculations are based on the standard statistical formula for Cronbach's Alpha. For more detailed analysis, consult a statistical guidebook or resources from academic institutions.

The Formula Explained

Cronbach's Alpha: \( \alpha = \frac{N}{N - 1} \left(1 - \frac{\sum \sigma_i^2}{\sigma_t^2}\right) \)

Glossary of Terms

Number of Items (N): Total number of questions or statements in the test.
Item Variances: Variance for each individual item.
Total Variance (σᵗ²): Variance for the entire set of items.

Frequently Asked Questions (FAQ)

What is Cronbach's Alpha?

Cronbach's Alpha is a measure of internal consistency, indicating how closely related a set of items are as a group.

How do you calculate Cronbach's Alpha?

It is calculated using the formula: \( \alpha = \frac{N}{N - 1} \left(1 - \frac{\sum \sigma_i^2}{\sigma_t^2}\right) \).

Tool developed by Ugo Candido. Content reviewed by the CalcDomain Expert Team.
Last reviewed for accuracy on: October 5, 2023.