Normal Distribution Calculator
Find probabilities for a normal distribution. The result updates as you type, with the working underneath so you can check it.
Your details
Result
Probability
0.84134
84.134%
Good to know: z = (x − μ) ÷ σ; P from the standard normal CDF
About this tool
Formula
z = (x − μ) ÷ σ; P from the standard normal CDF
Questions people ask
What is the 68-95-99.7 rule?
About 68% of values lie within 1 standard deviation of the mean, 95% within 2 and 99.7% within 3.
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How we calculate this
We use the standard published formula or definition for this calculation, and we show the working so you can check it.
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