Z-Table Reference

Find probabilities for Z-scores in the standard normal distribution

Z ↓.00.01.02.03.04.05.06.07.08.09
-4.00.00000.00000.00000.00000.00000.00000.00000.00000.00000.0000
-3.90.00000.00010.00010.00010.00010.00010.00010.00010.00010.0001
-3.80.00010.00010.00010.00010.00010.00010.00010.00010.00010.0001
-3.70.00010.00010.00010.00010.00010.00010.00010.00010.00010.0002
-3.60.00020.00020.00020.00020.00020.00020.00020.00020.00020.0002
-3.50.00020.00020.00030.00030.00030.00030.00030.00030.00030.0003
-3.40.00030.00030.00040.00040.00040.00040.00040.00040.00050.0005
-3.30.00050.00050.00050.00050.00060.00060.00060.00060.00060.0007
-3.20.00070.00070.00070.00080.00080.00080.00080.00090.00090.0009
-3.10.00100.00100.00100.00110.00110.00110.00120.00120.00130.0013
-3.00.00130.00140.00140.00150.00150.00160.00160.00170.00180.0018
-2.90.00190.00190.00200.00210.00210.00220.00230.00230.00240.0025
-2.80.00260.00260.00270.00280.00290.00300.00310.00320.00330.0034
-2.70.00350.00360.00370.00380.00390.00400.00410.00430.00440.0045
-2.60.00470.00480.00490.00510.00520.00540.00550.00570.00590.0060
-2.50.00620.00640.00660.00680.00690.00710.00730.00750.00780.0080
-2.40.00820.00840.00870.00890.00910.00940.00960.00990.01020.0104
-2.30.01070.01100.01130.01160.01190.01220.01250.01290.01320.0136
-2.20.01390.01430.01460.01500.01540.01580.01620.01660.01700.0174
-2.10.01790.01830.01880.01920.01970.02020.02070.02120.02170.0222
-2.00.02280.02330.02390.02440.02500.02560.02620.02680.02740.0281
-1.90.02870.02940.03010.03070.03140.03220.03290.03360.03440.0351
-1.80.03590.03670.03750.03840.03920.04010.04090.04180.04270.0436
-1.70.04460.04550.04650.04750.04850.04950.05050.05160.05260.0537
-1.60.05480.05590.05710.05820.05940.06060.06180.06300.06430.0655
-1.50.06680.06810.06940.07080.07210.07350.07490.07640.07780.0793
-1.40.08080.08230.08380.08530.08690.08850.09010.09180.09340.0951
-1.30.09680.09850.10030.10200.10380.10560.10750.10930.11120.1131
-1.20.11510.11700.11900.12100.12300.12510.12710.12920.13140.1335
-1.10.13570.13790.14010.14230.14460.14690.14920.15150.15390.1562
-1.00.15870.16110.16350.16600.16850.17110.17360.17620.17880.1814
-0.90.18410.18670.18940.19220.19490.19770.20050.20330.20610.2090
-0.80.21190.21480.21770.22060.22360.22660.22960.23270.23580.2389
-0.70.24200.24510.24830.25140.25460.25780.26110.26430.26760.2709
-0.60.27430.27760.28100.28430.28770.29120.29460.29810.30150.3050
-0.50.30850.31210.31560.31920.32280.32640.33000.33360.33720.3409
-0.40.34460.34830.35200.35570.35940.36320.36690.37070.37450.3783
-0.30.38210.38590.38970.39360.39740.40130.40520.40900.41290.4168
-0.20.42070.42470.42860.43250.43640.44040.44430.44830.45220.4562
-0.10.46020.46410.46810.47210.47610.48010.48400.48800.49200.4960
0.00.50000.50400.50800.51200.51600.51990.52390.52790.53190.5359
0.10.53980.54380.54780.55170.55570.55960.56360.56750.57140.5753
0.20.57930.58320.58710.59100.59480.59870.60260.60640.61030.6141
0.30.61790.62170.62550.62930.63310.63680.64060.64430.64800.6517
0.40.65540.65910.66280.66640.67000.67360.67720.68080.68440.6879
0.50.69150.69500.69850.70190.70540.70880.71230.71570.71900.7224
0.60.72570.72910.73240.73570.73890.74220.74540.74860.75170.7549
0.70.75800.76110.76420.76730.77040.77340.77640.77940.78230.7852
0.80.78810.79100.79390.79670.79950.80230.80510.80780.81060.8133
0.90.81590.81860.82120.82380.82640.82890.83150.83400.83650.8389
1.00.84130.84380.84610.84850.85080.85310.85540.85770.85990.8621
1.10.86430.86650.86860.87080.87290.87490.87700.87900.88100.8830
1.20.88490.88690.88880.89070.89250.89440.89620.89800.89970.9015
1.30.90320.90490.90660.90820.90990.91150.91310.91470.91620.9177
1.40.91920.92070.92220.92360.92510.92650.92790.92920.93060.9319
1.50.93320.93450.93570.93700.93820.93940.94060.94180.94290.9441
1.60.94520.94630.94740.94840.94950.95050.95150.95250.95350.9545
1.70.95540.95640.95730.95820.95910.95990.96080.96160.96250.9633
1.80.96410.96490.96560.96640.96710.96780.96860.96930.96990.9706
1.90.97130.97190.97260.97320.97380.97440.97500.97560.97610.9767
2.00.97720.97780.97830.97880.97930.97980.98030.98080.98120.9817
2.10.98210.98260.98300.98340.98380.98420.98460.98500.98540.9857
2.20.98610.98640.98680.98710.98750.98780.98810.98840.98870.9890
2.30.98930.98960.98980.99010.99040.99060.99090.99110.99130.9916
2.40.99180.99200.99220.99250.99270.99290.99310.99320.99340.9936
2.50.99380.99400.99410.99430.99450.99460.99480.99490.99510.9952
2.60.99530.99550.99560.99570.99590.99600.99610.99620.99630.9964
2.70.99650.99660.99670.99680.99690.99700.99710.99720.99730.9974
2.80.99740.99750.99760.99770.99770.99780.99790.99790.99800.9981
2.90.99810.99820.99820.99830.99840.99840.99850.99850.99860.9986
3.00.99870.99870.99870.99880.99880.99890.99890.99890.99900.9990
3.10.99900.99910.99910.99910.99920.99920.99920.99920.99930.9993
3.20.99930.99930.99940.99940.99940.99940.99940.99950.99950.9995
3.30.99950.99950.99950.99960.99960.99960.99960.99960.99960.9997
3.40.99970.99970.99970.99970.99970.99970.99970.99970.99970.9998
3.50.99980.99980.99980.99980.99980.99980.99980.99980.99980.9998
3.60.99980.99980.99990.99990.99990.99990.99990.99990.99990.9999
3.70.99990.99990.99990.99990.99990.99990.99990.99990.99990.9999
3.80.99990.99990.99990.99990.99990.99990.99990.99990.99990.9999
3.91.00001.00001.00001.00001.00001.00001.00001.00001.00001.0000
4.01.0000

What is a Z-Table?

A Z-table, also known as a standard normal table, is a mathematical tool that shows the probability of a standard normal random variable falling below a certain z-score. It's essential for:

  • Finding specific probabilities in a normal distribution
  • Converting between z-scores and probabilities
  • Making statistical inferences about normally distributed data
  • Calculating confidence intervals and p-values

Why Use a Z-Table?

Standardization

Convert any normal distribution to a standard form, making comparisons possible across different datasets.

Probability Analysis

Determine the likelihood of observations falling within specific ranges of a normal distribution.

Statistical Testing

Essential for hypothesis testing, confidence intervals, and other statistical procedures.

How to Use the Z-Table

  1. Find the row (Z) corresponding to the first two digits of your Z-score
  2. Move across to the column (.00 to .09) for the third decimal place
  3. The intersection shows the area to the left of that Z-score
  4. For negative Z-scores, use the absolute value and adjust accordingly

Common Z-Score Values

Z = ±1.96

Used for 95% confidence intervals. 95% of the data falls within 1.96 standard deviations of the mean.

Z = ±2.58

Used for 99% confidence intervals. 99% of the data falls within 2.58 standard deviations of the mean.