Find Z Score Calculator

Z-Score: 1.5.
Percentile: 93

Calculation Detail

Z = (Raw Score - Population Mean) / Standard Deviation
Z = (7 - 2.5) / 3

Tool Overview: Z Score Calculator

This Find Z Score calculator is used to convert your raw score into a standardized z score. This uses the Z score formula to automate the process of looking up this information in a z table. Enter the three factors (population mean, standard deviation, and raw score) into the calculator and it will generate the appropriate Z-Score. This standard score identifies where your raw score would fall in a standard normal distribution.

The find z score calculator will also convert your Z-score into an appropriate p-value, given in this case as percentile. This identifies the probability of seeing that raw score within a standard normal distribution, expressed as the percentage of the normal distribution under that mark. If you already have a Z-statistic and just need to calculate the p value, we have a simple p value calculator. We have another version that works for calculating the p value from a t statistic if you are working with small sample sizes and need to use Student's t-distribution.

For those of you using the find z score calculator to check statistics homework, we present a breakout of the relevant calculations. This includes both the formula and a version populated with numbers from the calculator. This is intended to help you check your calculations. It replaces a z table. If you're using R, check out the rnorm function.

Speaking as a practicing analyst, concepts such as a Z-Score can be very useful when comparing the performance of similar processes measured under different conditions. For example, a larger machine might have a different level of output than a smaller machine but swings and variation in that output could certainly vary based on similar factors. This type of analysis allows you to translate these differences into a common basis and make intelligent comparisons.

Other Tools: P Value From Z Score, P Value From T Score, Confidence Interval (proportion), t critical value calculator, z critical value calculator