What is the Cronbach’s Alpha Calculator?
Calculate Cronbach’s alpha from item variances and total-score variance. ITS Research Solution keeps the interactive tool above the explanation so you can calculate first and then review the method used.
Formula or method
α = k/(k−1) × [1 − Σ(item variances)/variance(total score)].
How to use this tool
Enter the requested values using consistent units, run the calculation and review the main result plus any supporting values. For a scale with multiple items, alpha summarizes internal consistency under its assumptions.
Interpretation and limitations
Alpha is not proof of unidimensionality or validity and should not be interpreted in isolation. Always check source data, units, rounding and discipline-specific requirements before using a result in assessed, published, regulated or high-stakes work.
Frequently asked questions
How is this result calculated?
u03b1 = k/(ku22121) u00d7 [1 u2212 u03a3(item variances)/variance(total score)].
Can I use this result in formal academic or research work?
Use it as a transparent calculation aid, then verify the assumptions, units, rounding and any institution-, journal- or field-specific requirements before formal use.