Normal DistributionLast updated: March 2026

Empirical Rule Calculator

Calculate the 68-95-99.7 rule (Empirical Rule) for normal distributions. Understand data spread in standard deviations.

Distribution Parameters

Mean (μ)

Center of the distribution

Standard Deviation (σ)

Spread of the distribution (must be positive)

1σ68.27%

Range

85.00 to 115.00

2σ95.45%

Range

70.00 to 130.00

3σ99.73%

Range

55.00 to 145.00

✓ What This Means

Related Tools

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Average value

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