Statistics Calculator

Paste data from a spreadsheet to get descriptive statistics, normality tests, t-tests, ANOVA, chi-square tests and correlation and regression, each with a one-line reading. Use it to compare means or check a p-value without statistics software.

How to use

1. Paste spreadsheet columns into "Data". A text first row becomes the column names, and each column is one group. "Load example" shows how it works.
2. Choose the "Significance level α": 0.01, 0.05 or 0.10.
3. Pick a tab ("Descriptive", "Normality", "t-test", "ANOVA", "Chi-square" or "Correlation & regression") and select the columns.
4. Read the table and the reading below it, and take the results with "Copy table".

How it works

• The t-test covers one sample, two independent samples and paired data. Two independent samples use Welch's t-test by default, with the confidence interval of the difference and Cohen's d.
• Normality uses Shapiro–Wilk and Anderson–Darling. ANOVA also shows an equal-variance test and Welch's ANOVA; a 2×2 table also gets Fisher's exact test.
• Quartiles match Excel QUARTILE.INC. Outliers are values below Q1 − 1.5×IQR or above Q3 + 1.5×IQR.
• This is for basic analysis and does not replace professional statistics software.

Questions and answers

What does a p-value below 0.05 mean?

At the 0.05 level, there is evidence of a difference or relationship. Whether it is large enough to matter is judged from the effect size and confidence interval.

When should I use an independent or a paired t-test?

Use two independent samples for separate groups, and the paired test for the same subjects measured twice. The paired test pairs values in the same row.

How do I compare the means of three or more groups?

Use one-way ANOVA. A small p-value means at least one mean differs, but not which one.

What is the difference between r and R²?

r gives the direction and strength of a straight-line relationship, from −1 to 1. R² is the share of the variation in Y explained by the line. In simple regression, R² = r².