Percentile to Z-Score Calculator

Enter the area under the normal curve (a proportion between 0 & 1) and get the Z-critical value, one-sided or two-sided.



 Shaded area has a z-score of
Proportion of AreaZ-Score
  
Decimal Points

Download this calculator in an excel file or take a Crash course in Z-scores

The values presented in the graphs above are approximations derived from the work of Abramowitz & Stegun. If you need precision to more that 6 decimals you are encouraged to consult multiple published tables of Z-Values.