The chi-square (χ²) test of independence checks whether two categorical variables are associated, for example gender and whether students use online learning (yes/no). Paste your table of counts and the calculator shows observed and expected counts, χ², degrees of freedom, the p-value, Cramér’s V and a warning if expected counts are too small.
How to use this calculator
- Build a crosstab of counts (not percentages): one variable in rows, the other in columns.
- Copy the table from Excel, including row and column labels if you like, and paste it.
- Click Calculate.
- Check the note under the table: expected counts should be at least 5 in most cells.
- Copy the APA sentence.
Formula
Eᵢⱼ = (row total × column total) / N χ² = Σ (O − E)² / E df = (rows − 1)(columns − 1) Cramér's V = √[χ² / (N · (min(rows, columns) − 1))]
Step-by-step example
- 100 students: Male 30 yes / 20 no, Female 18 yes / 32 no.
- Expected counts: 24 and 26 in each row.
- χ²(1, N = 100) = 5.77, p = .016.
- Cramér’s V = .24 (a small-to-medium association).
How to interpret the results
If p is below .05, the two variables are associated: the distribution of one depends on the other. Compare observed and expected counts to see where the association comes from (cells where observed is much higher than expected). Cramér’s V shows the strength: for a 2×2 table about .10 is small, .30 medium and .50 large.
How to report it in APA 7 style
A chi-square test of independence showed a significant association between gender and use of online learning, χ²(1, N = 100) = 5.77, p = .016, Cramér’s V = .24.
Statistical symbols (t, F, p, r, M, SD, N, d) should be italicised in your thesis.
Assumptions
- Both variables are categorical.
- Each participant is counted in only one cell (independent observations).
- Expected counts are 5 or more in at least 80% of cells and none is below 1; for small 2×2 tables use Fisher’s exact test.
- Data are frequencies (counts), not percentages or means.
How to do it in SPSS, R or Excel
SPSS: Analyze → Descriptive Statistics → Crosstabs → Statistics → Chi-square, Phi and Cramér’s V. R: chisq.test(table, correct = FALSE). Excel: =CHISQ.TEST(observed, expected).
Roman Urdu mein khulasa
Chi-square test check karta hai ke do categorical variables (jaise gender aur haan/nahi jawab) aapas mein jure hue hain ya nahi. Excel mein counts ki table banayein (percentages nahi) aur paste karein. p 0.05 se kam ho to association significant hai. Cramér’s V batata hai ke rishta kitna mazboot hai. Har cell ka expected count 5 ya zyada hona behtar hai.
Frequently asked questions
Can I use percentages in a chi-square test?
No. The chi-square test needs raw counts (frequencies). Convert percentages back to counts before pasting.
What if some expected counts are below 5?
If more than 20% of cells have expected counts below 5, the chi-square approximation is unreliable. For 2×2 tables use Fisher’s exact test, or merge categories in larger tables.
Does this calculator apply Yates’ continuity correction?
No. It reports the Pearson chi-square without continuity correction, which matches the first row of SPSS output. Yates’ correction is conservative and less recommended today.
What is Cramér’s V?
Cramér’s V is an effect size for chi-square that ranges from 0 (no association) to 1 (perfect association). For 2×2 tables it equals the absolute value of phi.
What is the difference between chi-square independence and goodness of fit?
The test of independence compares two categorical variables in a crosstab. The goodness-of-fit test compares one variable’s observed counts against expected proportions.
How do I report chi-square in APA?
Write χ²(df, N = total) = value, p = value, followed by the effect size, e.g. χ²(1, N = 100) = 5.77, p = .016, Cramér’s V = .24.
Related calculators
- Pearson Correlation Calculator
- Descriptive Statistics Calculator
- Sample Size Calculator for Thesis
- Not sure which test to use? Try the test chooser
Cite this calculator
If ScholarCalc helped your analysis, you can cite it in APA 7 format:
ScholarCalc. (2026). Chi-Square Test of Independence Calculator [Web application]. https://scholarcalc.com/chi-square-calculator/
Written and maintained by the ScholarCalc team. Last reviewed: November 2026.
Accuracy: results are computed in your browser and were validated against Python scipy, statsmodels and pingouin on test datasets. See Methodology and accuracy.