Z Table | Z Score Table PDF

Use this Z table (standard normal distribution table) to find probabilities Includes full positive and negative Z score tables for quick lookup.

The Z Table (also called standard normal table or z score table) helps you find probabilities for values in a standard normal distribution. It shows the area under the curve to the left of any Z score.

Students, teachers, and researchers use it daily for statistics problems, hypothesis testing, and confidence intervals. This page gives you both positive and negative Z score tables so you can look up exact values quickly and accurately.

What Is a Z Table?

A Z table, also called a standard normal table or z score table, lists probabilities for the standard normal distribution. It shows the area under the bell curve to the left of any Z score.

The standard normal distribution has a mean of 0 and a standard deviation of 1. Z scores tell you how far a value is from the mean in standard deviation units.

Real-world example If a student’s test score is 1.5 standard deviations above the mean, their Z score is 1.5. The Z table tells you what percentage of students scored below that value.

This makes the Z table essential for finding probabilities in statistics without complex math.

How to Use a Z Table

A Z table shows the probability (area under the curve) to the left of a Z score. Follow these steps to read it correctly.

Step 1: Find your Z score. Round it to two decimal places if needed.
Step 2: Look at the first column and row for the whole number and first decimal (example: 1.5 goes to row 1.5).
Step 3: Move across the top row to the second decimal place (example: 1.96 → column 0.06).
Step 4: Read the number in that cell. This is the probability P(Z < your score).

For negative Z scores: Use the negative Z table (or flip the sign and use the positive table, since the distribution is symmetric). The probability is still the area to the left.

Quick tip Most tables give cumulative probability from -∞ to Z. To find P(Z > z), subtract the table value from 1.

Practice with the positive and negative Z score tables below to get comfortable.

Negative Z Score Table (z < 0) – Area to the LEFT of z

This negative Z score table shows the cumulative probability P(Z < z) for Z scores from -3.09 to 0.00. Look up the row and column the same way as the positive table. The value is the area to the left of the negative Z score.

Use this table for Negative Z scores only. For Postive scores, see the next section or use symmetry.

z.00.01.02.03.04.05.06.07.08.09
-3.90.000050.000050.000040.000040.000040.000040.000040.000040.000030.00003
-3.80.000070.000070.000070.000060.000060.000060.000060.000050.000050.00005
-3.70.000110.000100.000100.000100.000090.000090.000080.000080.000080.00008
-3.60.000160.000150.000150.000140.000140.000130.000130.000120.000120.00011
-3.50.000230.000220.000220.000210.000200.000190.000190.000180.000170.00017
-3.40.000340.000320.000310.000300.000290.000280.000270.000260.000250.00024
-3.30.000480.000470.000450.000430.000420.000400.000390.000380.000360.00035
-3.20.000690.000660.000640.000620.000600.000580.000560.000540.000520.00050
-3.10.000970.000940.000900.000870.000840.000820.000790.000760.000740.00071
-3.00.001350.001310.001260.001220.001180.001140.001110.001070.001040.00100
-2.90.001870.001810.001750.001690.001640.001590.001540.001490.001440.00139
-2.80.002560.002480.002400.002330.002260.002190.002120.002050.001990.00193
-2.70.003470.003360.003260.003170.003070.002980.002890.002800.002720.00264
-2.60.004660.004530.004400.004270.004150.004020.003910.003790.003680.00357
-2.50.006210.006040.005870.005700.005540.005390.005230.005080.004940.00480
-2.40.008200.007980.007760.007550.007340.007140.006950.006760.006570.00639
-2.30.010720.010440.010170.009900.009640.009390.009140.008890.008660.00842
-2.20.013900.013550.013210.012870.012550.012220.011910.011600.011300.01101
-2.10.017860.017430.017000.016590.016180.015780.015390.015000.014630.01426
-2.00.022750.022220.021690.021180.020680.020180.019700.019230.018760.01831
-1.90.028720.028070.027430.026800.026190.025590.025000.024420.023850.02330
-1.80.035930.035150.034380.033620.032880.032160.031440.030740.030050.02938
-1.70.044570.043630.042720.041820.040930.040060.039200.038360.037540.03673
-1.60.054800.053700.052620.051550.050500.049470.048460.047460.046480.04551
-1.50.066810.065520.064260.063010.061780.060570.059380.058210.057050.05592
-1.40.080760.079270.077800.076360.074930.073530.072150.070780.069440.06811
-1.30.096800.095100.093420.091760.090120.088510.086910.085340.083790.08226
-1.20.115070.113140.111230.109350.107490.105650.103830.102040.100270.09853
-1.10.135670.133500.131360.129240.127140.125070.123020.121000.119000.11702
-1.00.158660.156250.153860.151510.149170.146860.144570.142310.140070.13786
-0.90.184060.181410.178790.176190.173610.171060.168530.166020.163540.16109
-0.80.211860.208970.206110.203270.200450.197660.194890.192150.189430.18673
-0.70.241960.238850.235760.232700.229650.226630.223630.220650.217700.21476
-0.60.274250.270930.267630.264350.261090.257850.254630.251430.248250.24510
-0.50.308540.305030.301530.298060.294600.291160.287740.284340.280960.27760
-0.40.344580.340900.337240.333600.329970.326360.322760.319180.315610.31207
-0.30.382090.378280.374480.370700.366930.363170.359420.355690.351970.34827
-0.20.420740.416830.412940.409050.405170.401290.397430.393580.389740.38591
-0.10.460170.456200.452240.448280.444330.440380.436440.432510.428580.42465
-0.00.500000.496010.492020.488030.484050.480060.476080.472100.468120.46414

Positive Z Score Table(z ≥ 0) – Area to the LEFT of z

This positive Z score table shows the cumulative probability P(Z < z) for Z scores from 0.00 to 3.09. Look up the first digit and first decimal in the left column, then find the second decimal in the top row. The value in the cell is the area to the left of that Z score.

Use this table for positive Z scores only. For negative scores, see the above section or use symmetry.

z.00.01.02.03.04.05.06.07.08.09
0.00.500000.503990.507980.511970.515950.519940.523920.527900.531880.53586
0.10.539830.543800.547760.551720.555670.559620.563560.567490.571420.57535
0.20.579260.583170.587060.590950.594830.598710.602570.606420.610260.61409
0.30.617910.621720.625520.629300.633070.636830.640580.644310.648030.65173
0.40.655420.659100.662760.666400.670030.673640.677240.680820.684390.68793
0.50.691460.694970.698470.701940.705400.708840.712260.715660.719040.72240
0.60.725750.729070.732370.735650.738910.742150.745370.748570.751750.75490
0.70.758040.761150.764240.767300.770350.773370.776370.779350.782300.78524
0.80.788140.791030.793890.796730.799550.802340.805110.807850.810570.81327
0.90.815940.818590.821210.823810.826390.828940.831470.833980.836460.83891
1.00.841340.843750.846140.848490.850830.853140.855430.857690.859930.86214
1.10.864330.866500.868640.870760.872860.874930.876980.879000.881000.88298
1.20.884930.886860.888770.890650.892510.894350.896170.897960.899730.90147
1.30.903200.904900.906580.908240.909880.911490.913090.914660.916210.91774
1.40.919240.920730.922200.923640.925070.926470.927850.929220.930560.93189
1.50.933190.934480.935740.936990.938220.939430.940620.941790.942950.94408
1.60.945200.946300.947380.948450.949500.950530.951540.952540.953520.95449
1.70.955430.956370.957280.958180.959070.959940.960800.961640.962460.96327
1.80.964070.964850.965620.966380.967120.967840.968560.969260.969950.97062
1.90.971280.971930.972570.973200.973810.974410.975000.975580.976150.97670
2.00.977250.977780.978310.978820.979320.979820.980300.980770.981240.98169
2.10.982140.982570.983000.983410.983820.984220.984610.985000.985370.98574
2.20.986100.986450.986790.987130.987450.987780.988090.988400.988700.98899
2.30.989280.989560.989830.990100.990360.990610.990860.991110.991340.99158
2.40.991800.992020.992240.992450.992660.992860.993050.993240.993430.99361
2.50.993790.993960.994130.994300.994460.994610.994770.994920.995060.99520
2.60.995340.995470.995600.995730.995850.995980.996090.996210.996320.99643
2.70.996530.996640.996740.996830.996930.997020.997110.997200.997280.99736
2.80.997440.997520.997600.997670.997740.997810.997880.997950.998010.99807
2.90.998130.998190.998250.998310.998360.998410.998460.998510.998560.99861
3.00.998650.998690.998740.998780.998820.998860.998890.998930.998960.99900
3.10.999030.999060.999100.999130.999160.999180.999210.999240.999260.99929
3.20.999310.999340.999360.999380.999400.999420.999440.999460.999480.99950
3.30.999520.999530.999550.999570.999580.999600.999610.999620.999640.99965
3.40.999660.999670.999680.999690.999700.999710.999720.999730.999740.99975
3.50.999770.999780.999780.999790.999800.999810.999810.999820.999830.99983
3.60.999840.999850.999850.999860.999860.999870.999870.999880.999880.99989
3.70.999890.999900.999900.999900.999910.999910.999920.999920.999920.99992
3.80.999930.999930.999930.999940.999940.999940.999940.999950.999950.99995
3.90.999950.999950.999960.999960.999960.999960.999960.999960.999970.99997

For z values beyond ±3.9, the probability is essentially 0.0000 or 1.0000. Use statistical software (Excel, Python, R) for extreme values

Z Score to Probability Examples

These examples show how to use the Z table to find probabilities in the standard normal distribution.

Example 1: Probability less than a positive Z score

Find P(Z < 1.96). Look in the positive Z table. Row 1.9, column 0.06. The value is 0.9750.

This means 97.50% of values are less than 1.96 standard deviations above the mean.

Example 2: Probability greater than a negative Z score

Find P(Z > -1.28). Use symmetry: P(Z > -1.28) = P(Z < 1.28). Row 1.2, column 0.08. The value is 0.8997.

So about 89.97% of values are greater than -1.28.

Example 3: Probability between two Z scores

Find P(-1.5 < Z < 1.5). First, P(Z < 1.5) = 0.9332 (row 1.5, column 0.00). Then, P(Z < -1.5) = 1 – 0.9332 = 0.0668. Subtract: 0.9332 – 0.0668 = 0.8664.

This means 86.64% of values fall between -1.5 and 1.5 standard deviations.

Practice these lookups with the positive and negative Z tables above.

Common Mistakes When Reading a Z Table

Many beginners make these errors when using a Z table. Avoid them for correct probability results.

  • Confusing rows and columns. Always use the left column for the first two digits of Z and the top row for the second decimal.
  • Forgetting symmetry for negative Z scores. Use the positive table and subtract from 1 for P(Z > -z).
  • Looking up the wrong probability. The table gives P(Z < z), the area to the left. Subtract from 1 for right-tail areas.
  • Not rounding Z correctly. Round to two decimal places before looking up.
  • Adding areas incorrectly for ranges. For P(a < Z < b), subtract P(Z < a) from P(Z < b).
  • Using the Z table for non-standard normal distributions. Standardize first with z = (x − μ) / σ.

Double-check your lookup steps every time.

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