Standard score

z = (x − μ) / σ. σ must be non-zero.

FAQ

What does this tool do?

Browser-side helper for quick estimates. Read labels and disclaimers.

How accurate is it?

Educational only; rounding and assumptions may differ from production systems.

Where do inputs go?

Nothing is uploaded; calculations run locally in your browser.

Can I rely on this for legal, tax, or medical decisions?

No. Use qualified professionals when stakes are high.

Why do results differ from another site?

Different formulas, rounding, or definitions—compare assumptions.

Privacy

Inputs stay on your device unless your browser or extensions do otherwise.