used by people in more than 220 countries!
Calculator: Two-Tailed Area Under the Standard Normal Distribution
Two-Tailed Area Under the Standard Normal Distribution Calculator
This calculator will tell you the two-tailed area under the standard normal curve, given a Z-score (i.e., the two-tailed probability from +/- the Z-score to infinity on both tails of the distribution).
Please enter the necessary parameter values, and then click 'Calculate'.