Z-Score Calculator

All tools

Convert any value into a standard z-score using the mean and standard deviation, then read its percentile, the percentage above and the two-tailed p-value. Free and instant.

Must be greater than zero.
Z-score –
Percentile (below) –
Percentage above –
Two-tailed p-value –
Assumes a normal distribution. The z-score is (x − μ) ⁄ σ. The percentile uses an erf approximation of the standard normal CDF and is accurate to a few decimal places.
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