T-Score Calculator
t = (x̄ − μ₀) / (s/√n) — for testing a sample mean against a hypothesized population mean.
Result
General calculation reads
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How to use this calculator
- Enter sample mean, hypothesized population mean, sample SD, and sample size.
- Read the t-statistic and compare to a t-table at the right df.
About this calculator
t-score is to t-distribution what z-score is to normal — but t accounts for the additional uncertainty when σ is estimated from a small sample. Use t when σ is unknown and sample size is < 30; use z for large samples or known σ.
Frequently asked
When do I use t vs z?+
What is df (degrees of freedom)?+
How do I get a p-value from t?+
Is |t| > 2 always significant?+
What's the standard error?+
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