Z-Score Table for Statistics
Look up a z-score’s cumulative probability, percentile, and right-tail area, then use the full standard normal table below to see exactly where the value comes from.
Written and checked by TheToolNet Editorial Team · Last reviewed: September 12, 2026 · How we check statistics tools
Each entry is the area under the standard normal curve to the left of z. Multiply by 100 to express that area as a percentile.
Z-score table lookup
Enter any z-score from −8 to 8. The tool uses the standard normal cumulative distribution and verifies that the two tails add to 1.
Standard normal z-score chart
This positive-z table gives left cumulative area. For example, row 1.9 and column .06 meet at 0.9750, so a z-score of 1.96 is at about the 97.5th percentile.
| z | .00 | .01 | .02 | .03 | .04 | .05 | .06 | .07 | .08 | .09 |
|---|
How to read a z-score table
- Round z to two decimal places.
- Use the ones and tenths digits for the row. For z = 1.96, choose row 1.9.
- Use the hundredths digit for the column. Choose column .06.
- Read the intersection: Φ(1.96) ≈ 0.9750.
A left area of 0.9750 means about 97.5% of a standard normal distribution lies below 1.96. The right tail is 1 − 0.9750 = 0.0250.
How to find a negative z-score
The standard normal distribution is symmetric, so Φ(−z) = 1 − Φ(z). For z = −1.96, look up 1.96 to get 0.9750, then calculate 1 − 0.9750 = 0.0250. The lookup calculator performs this step without rounding the intermediate value.
Need values between two cutoffs or a percentile-to-z conversion? Use the z distribution calculator.
Common z-scores and percentiles
| z | Left area | Percentile | Common use |
|---|---|---|---|
| 0 | 0.5000 | 50th | Distribution mean |
| 1.282 | ≈ 0.9000 | 90th | One-sided 10% tail |
| 1.645 | ≈ 0.9500 | 95th | One-sided 5% tail |
| 1.960 | ≈ 0.9750 | 97.5th | Two-sided 5% tails |
| 2.576 | ≈ 0.9950 | 99.5th | Two-sided 1% tails |
These are standard normal reference values, not a substitute for checking whether a normal model is appropriate for the data.
Frequently asked questions
What is the difference between a z table and a z chart?
They usually mean the same tabular reference. Some sources call it a standard normal table, z-score table, or z-score chart.
Does every z table report the same area?
No. Some tables report left cumulative area, while others report the area between zero and z or a tail area. Check the heading. This page always reports left cumulative area.
Why does my table differ in the last digit?
Printed tables round probabilities, commonly to four decimal places. The calculator keeps more precision, so a tiny difference is expected.