IA statistics · interactive tool

Analyse my data: statistics for your IA, step by step

Paste your data or upload a CSV and say what you want to find out. You get summary statistics, a graph, the test that fits, the condition checks with plain warnings, the working, the p-value and the critical value — and the questions to answer in your own interpretation.

Private by design: the calculations run in your browser. Nothing you type or upload is sent to our server unless you sign in and press Save.

1. Your data Paste columns from a spreadsheet, Desmos table or CSV (one row per person or thing; a heading row is read as column names)

Numbers or category labels, separated by commas, tabs or spaces. Up to 2000 rows.

Or upload a CSV fileOr load example data

2. Your question What do you want to find out?

More options

Significance level Alternative hypothesis

Expected proportions for “fit” (blank = all equal; or ratios in category order, e.g. 31, 28, 31, 30) Also show Welch's t-test (beyond the syllabus)

Free without an account: every question on the example data, and describing data and relationships on your own data. A free account unlocks every test on your own data and saving.

My saved analyses

How the tool works

It reads your columns and works out which are numbers and which are categories, then suggests the question that fits (you can change it).
Describe: mean, median, quartiles (the GDC method), IQR, σ and s, the 1.5 × IQR fences and a box plot and histogram.
Relationship: Pearson's r, r², the regression line of y on x and Spearman's rank, with a scatter graph.
Groups: the pooled two-sample t-test (and Welch's if you ask); paired: a t-test on the differences; categories: the χ² test for independence; fit: the χ² goodness-of-fit test.
Every test checks its conditions on your data and warns you in plain words (expected frequencies below 5, small samples, very different spreads, a curved scatter graph).

Each technique has a worked page explaining it in full: choosing the right test, sampling and collecting data, cleaning data and outliers, box plots and comparing distributions, correlation and regression, spearman's rank, χ² test for independence, χ² goodness of fit, t-test, normal distribution checks, confidence intervals, binomial and poisson models. Need data? Try the IA data bank.

Frequently asked questions

Can I use Analyse my data for my IA?

Use it to learn the method and to check your own working. Your IA must show your own working and your own interpretation; the tool gives prompts and sentence openings, never the interpretation. Acknowledge it if your school's policy asks you to.

Is my data uploaded or saved?

Only if you choose to save it. Everything is calculated in your browser; a CSV you choose is read by your browser, not uploaded. Nothing is sent to our server unless you are signed in and press Save; then the data, your question, the result summary, your ticks and your note are kept in your account, and you can delete them at any time under My saved analyses.

Why might my GDC's answer differ slightly?

Rounding, a different quartile method (some software includes the median in both halves), or a different test version (pooled or unpooled t-test, with or without Yates' correction). The tool states the method it uses at each step.