Normal Cumulative Probability
Convert a normal-distribution threshold into a percentile.
Your numbers
Probability below threshold
Use consistent units. The result follows the assumptions you enter.
Scenario comparison
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Formula
z=(x−μ)/σ; P(X≤x)=Φ(z)
Convert a normal-distribution threshold into a percentile.
Worked example
- Mean μ
- 100
- Standard deviation σ
- 15
- Threshold x
- 115
- Probability below threshold
- 84.1344746069 %
- Probability above threshold
- 15.8655253931 %
- Standard score
- 1
Scope and limitations
Use consistent units. The result follows the assumptions you enter.
Inputs are checked for missing values and allowed ranges. A result outside the finite numeric range is not displayed. Rounding affects display, while the calculation uses the model’s numeric precision.
Check your units and assumptions before relying on a result. Changing a label does not convert a currency or physical unit.
Formula version: 616d2b8b7cc9 · Example checked: