Paired T-Test Calculator

Added 2026-08-29

Run a paired t-test on matched observations with paired mean difference, confidence interval and standardized effect size.

✓ Runs locally in your browser✓ No account or dataset upload required✓ Effect sizes / uncertainty shown where appropriate

Condition / beforeNumbers may be separated by commas, spaces, semicolons or new lines.

Condition / afterNumbers may be separated by commas, spaces, semicolons or new lines.

Confidence level

t statistic

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Two-sided p

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Mean paired difference

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Difference CI

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Cohen’s dz

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Statistical output is a calculation aid. Check assumptions, study design and reporting requirements before drawing scientific conclusions.

Small time-saver of the dayCtrl + Y / Ctrl + Shift + ZCtrl + Y / Ctrl + Shift + Z: Redo an action after Undo

Use Ctrl + Y / Ctrl + Shift + Z to redo an action after Undo. A small habit that keeps keyboard-heavy work moving.

About this tool

Run a paired t-test on matched observations with paired mean difference, confidence interval and standardized effect size.

Common uses

paired t test calculatorpaired samples t testdependent t test calculatorbefore after t test calculator

How it works

1Enter or paste the requested sample values, summary inputs or contingency data.
2Choose the method, confidence level or test options when available, then run the calculation.
3Review the estimate/test statistic together with p-value, confidence interval, effect size and method notes where available.

Does this statistics calculation upload my data?

No. Entered values are processed locally in your browser with JavaScript.

Should I interpret statistical significance by itself?

No. Review effect size, confidence intervals, study design, assumptions, sampling and multiplicity together with the p-value.