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One-Sample T-Test Calculator

Compute the one-sample t-statistic to test whether your sample mean differs significantly from a known or hypothesised population mean. The first inferential test most students learn — used in survey analysis, quality control, and any single-group comparison against a benchmark.

Sample Mean

Population Mean (H₀)

Sample Standard Deviation

Sample Size

Fill in the required fields to see your result.

Statistics

Confidence Interval Calculator

Compute the margin of error around a sample mean for a 90%, 95%, or 99% confidence interval using the z-distribution. The half-width of the CI tells you how precisely your sample estimates the population mean — essential for survey reporting, scientific publication, and any inference.

Sample Size (n)

Standard Deviation

Confidence Level

Fill in the required fields to see your result.

Key differences

	One-Sample T-Test Calculator	Confidence Interval Calculator
Category	Statistics	Statistics
Inputs required	4	3
Result	T-Statistic	Margin of Error (±)
What it does	Compute the one-sample t-statistic to test whether your sample mean differs significantly from a known or hypothesised population mean. The first inferential test most students learn — used in survey analysis, quality control, and any single-group comparison against a benchmark.	Compute the margin of error around a sample mean for a 90%, 95%, or 99% confidence interval using the z-distribution. The half-width of the CI tells you how precisely your sample estimates the population mean — essential for survey reporting, scientific publication, and any inference.