Z-test Calculator

One-sample • Two-sample • p-value • Critical z • Ajax loading • Hard reset

Live

Settings

🧪 Test type

α is optional (default 0.05) to show critical z threshold(s).

Quick summary

Enter summary stats to compute Z-test.

📌 One-sample inputs

x̄

μ₀

σ must be known (population SD). n must be integer ≥ 1.

📌 Two-sample inputs

x̄₁

x̄₂

σ₁

σ₂

n₁

n₂

Δ₀

Δ₀ is hypothesized (μ₁−μ₂). Use 0 for “no difference”.

Results

z statistic

—

p-value

—

Standard error (SE)

—

Effect

—

Critical z

—

Based on α and tail selection.

Decision

—

“Reject H₀” if p ≤ α (α default 0.05).

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Action

Hard reset: cancels pending updates and clears everything on the first click.

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