Education

Normal Distribution Calculator

Z-scores, probabilities below/above/between values, and inverse normal.

Education

Local only

Mean (μ)Standard deviation (σ)Findx (or x₁, or probability for inverse)x₂ (between)

Everything stays in your browser

Your text is processed on your device — nothing is uploaded to a server.

How it works

CDF via a high-precision erf approximation (error < 1.2e-7); inverse by bisection.

Good to know

How do I use it?

Fill in the options and press “Calculate”. Check the result, then copy or download it.

How does it work?

CDF via a high-precision erf approximation (error < 1.2e-7); inverse by bisection.

Is my data uploaded?

No. Everything is processed in your browser and nothing is sent to a server. No account is needed.