Chi Square Calculator
Free Chi square Calculator for biostatistics. Enter variables to compute results with formulas and detailed steps. Get results you can export or share.
Formula
ฯยฒ = ฮฃ[(Oแตข - Eแตข)ยฒ / Eแตข] | df = k - 1 (goodness-of-fit)
Chi-square goodness-of-fit test compares observed frequencies to expected frequencies. Large ฯยฒ means observed differs significantly from expected. If no expected values given, assumes equal distribution.
Frequently Asked Questions
How do I use a Punnett square?
A Punnett square predicts offspring genotype ratios. Write one parent's alleles across the top and the other's down the side. Fill in each box by combining the row and column alleles. For a monohybrid cross of two heterozygotes (Aa x Aa), you get 1 AA : 2 Aa : 1 aa, or a 3:1 phenotype ratio.
What formula does Chi Square Calculator use?
The formula used is described in the Formula section on this page. It is based on widely accepted standards in the relevant field. If you need a specific reference or citation, the References section provides links to authoritative sources.
How do I get the most accurate result?
Enter values as precisely as possible using the correct units for each field. Check that you have selected the right unit (e.g. kilograms vs pounds, meters vs feet) before calculating. Rounding inputs early can reduce output precision.
Can I use Chi Square Calculator on a mobile device?
Yes. All calculators on NovaCalculator are fully responsive and work on smartphones, tablets, and desktops. The layout adapts automatically to your screen size.
Can I share or bookmark my calculation?
You can bookmark the calculator page in your browser. Many calculators also display a shareable result summary you can copy. The page URL stays the same so returning to it will bring you back to the same tool.
How do I interpret the result?
Results are displayed with a label and unit to help you understand the output. Many calculators include a short explanation or classification below the result (for example, a BMI category or risk level). Refer to the worked examples section on this page for real-world context.