How to read the table: each cell shows the quantile χ²(p,ν) such that P(X ≤ χ²) = p. For a goodness-of-fit test at the 5% level with ν = 10 degrees of freedom, look up the column p = 0.950 → χ² = 18.307.
Click a cell to see the critical value.
χ²(p, ν) — quantiles for p = P(X ≤ χ²)
| ν (gl) | p = 0.005 | p = 0.01 | p = 0.025 | p = 0.05 | p = 0.1 | p = 0.9 | p = 0.95 | p = 0.975 | p = 0.99 | p = 0.995 |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 0.000 | 0.000 | 0.001 | 0.004 | 0.016 | 2.706 | 3.841 | 5.024 | 6.635 | 7.879 |
| 2 | 0.010 | 0.020 | 0.051 | 0.103 | 0.211 | 4.605 | 5.991 | 7.378 | 9.210 | 10.597 |
| 3 | 0.072 | 0.115 | 0.216 | 0.352 | 0.584 | 6.251 | 7.815 | 9.348 | 11.345 | 12.838 |
| 4 | 0.207 | 0.297 | 0.484 | 0.711 | 1.064 | 7.779 | 9.488 | 11.143 | 13.277 | 14.860 |
| 5 | 0.412 | 0.554 | 0.831 | 1.145 | 1.610 | 9.236 | 11.070 | 12.833 | 15.086 | 16.750 |
| 6 | 0.676 | 0.872 | 1.237 | 1.635 | 2.204 | 10.645 | 12.592 | 14.449 | 16.812 | 18.548 |
| 7 | 0.989 | 1.239 | 1.690 | 2.167 | 2.833 | 12.017 | 14.067 | 16.013 | 18.475 | 20.278 |
| 8 | 1.344 | 1.646 | 2.180 | 2.733 | 3.490 | 13.362 | 15.507 | 17.535 | 20.090 | 21.955 |
| 9 | 1.735 | 2.088 | 2.700 | 3.325 | 4.168 | 14.684 | 16.919 | 19.023 | 21.666 | 23.589 |
| 10 | 2.156 | 2.558 | 3.247 | 3.940 | 4.865 | 15.987 | 18.307 | 20.483 | 23.209 | 25.188 |
| 11 | 2.603 | 3.053 | 3.816 | 4.575 | 5.578 | 17.275 | 19.675 | 21.920 | 24.725 | 26.757 |
| 12 | 3.074 | 3.571 | 4.404 | 5.226 | 6.304 | 18.549 | 21.026 | 23.337 | 26.217 | 28.300 |
| 13 | 3.565 | 4.107 | 5.009 | 5.892 | 7.042 | 19.812 | 22.362 | 24.736 | 27.688 | 29.819 |
| 14 | 4.075 | 4.660 | 5.629 | 6.571 | 7.790 | 21.064 | 23.685 | 26.119 | 29.141 | 31.319 |
| 15 | 4.601 | 5.229 | 6.262 | 7.261 | 8.547 | 22.307 | 24.996 | 27.488 | 30.578 | 32.801 |
| 16 | 5.142 | 5.812 | 6.908 | 7.962 | 9.312 | 23.542 | 26.296 | 28.845 | 32.000 | 34.267 |
| 17 | 5.697 | 6.408 | 7.564 | 8.672 | 10.085 | 24.769 | 27.587 | 30.191 | 33.409 | 35.718 |
| 18 | 6.265 | 7.015 | 8.231 | 9.390 | 10.865 | 25.989 | 28.869 | 31.526 | 34.805 | 37.156 |
| 19 | 6.844 | 7.633 | 8.907 | 10.117 | 11.651 | 27.204 | 30.144 | 32.852 | 36.191 | 38.582 |
| 20 | 7.434 | 8.260 | 9.591 | 10.851 | 12.443 | 28.412 | 31.410 | 34.170 | 37.566 | 39.997 |
| 21 | 8.034 | 8.897 | 10.283 | 11.591 | 13.240 | 29.615 | 32.671 | 35.479 | 38.932 | 41.401 |
| 22 | 8.643 | 9.542 | 10.982 | 12.338 | 14.041 | 30.813 | 33.924 | 36.781 | 40.289 | 42.796 |
| 23 | 9.260 | 10.196 | 11.689 | 13.091 | 14.848 | 32.007 | 35.172 | 38.076 | 41.638 | 44.181 |
| 24 | 9.886 | 10.856 | 12.401 | 13.848 | 15.659 | 33.196 | 36.415 | 39.364 | 42.980 | 45.559 |
| 25 | 10.520 | 11.524 | 13.120 | 14.611 | 16.473 | 34.382 | 37.652 | 40.646 | 44.314 | 46.928 |
| 26 | 11.160 | 12.198 | 13.844 | 15.379 | 17.292 | 35.563 | 38.885 | 41.923 | 45.642 | 48.290 |
| 27 | 11.808 | 12.879 | 14.573 | 16.151 | 18.114 | 36.741 | 40.113 | 43.195 | 46.963 | 49.645 |
| 28 | 12.461 | 13.565 | 15.308 | 16.928 | 18.939 | 37.916 | 41.337 | 44.461 | 48.278 | 50.993 |
| 29 | 13.121 | 14.256 | 16.047 | 17.708 | 19.768 | 39.087 | 42.557 | 45.722 | 49.588 | 52.336 |
| 30 | 13.787 | 14.953 | 16.791 | 18.493 | 20.599 | 40.256 | 43.773 | 46.979 | 50.892 | 53.672 |
| 35 | 17.192 | 18.509 | 20.569 | 22.465 | 24.797 | 46.059 | 49.802 | 53.203 | 57.342 | 60.275 |
| 40 | 20.707 | 22.164 | 24.433 | 26.509 | 29.051 | 51.805 | 55.758 | 59.342 | 63.691 | 66.766 |
| 45 | 24.311 | 25.901 | 28.366 | 30.612 | 33.350 | 57.505 | 61.656 | 65.410 | 69.957 | 73.166 |
| 50 | 27.991 | 29.707 | 32.357 | 34.764 | 37.689 | 63.167 | 67.505 | 71.420 | 76.154 | 79.490 |
| 60 | 35.534 | 37.485 | 40.482 | 43.188 | 46.459 | 74.397 | 79.082 | 83.298 | 88.379 | 91.952 |
| 70 | 43.275 | 45.442 | 48.758 | 51.739 | 55.329 | 85.527 | 90.531 | 95.023 | 100.425 | 104.215 |
| 80 | 51.172 | 53.540 | 57.153 | 60.391 | 64.278 | 96.578 | 101.879 | 106.629 | 112.329 | 116.321 |
| 90 | 59.196 | 61.754 | 65.647 | 69.126 | 73.291 | 107.565 | 113.145 | 118.136 | 124.116 | 128.299 |
| 100 | 67.328 | 70.065 | 74.222 | 77.929 | 82.358 | 118.498 | 124.342 | 129.561 | 135.807 | 140.169 |
| 120 | 83.852 | 86.923 | 91.573 | 95.705 | 100.624 | 140.233 | 146.567 | 152.211 | 158.950 | 163.648 |
| 150 | 109.142 | 112.668 | 117.985 | 122.692 | 128.275 | 172.581 | 179.581 | 185.800 | 193.208 | 198.360 |
| 200 | 152.241 | 156.432 | 162.728 | 168.279 | 174.835 | 226.021 | 233.994 | 241.058 | 249.445 | 255.264 |
How to read the table: each cell shows P(X ≤ x) for the selected degrees of freedom. The row gives the integer part of x; the column adds the first decimal (×0.1).
Click a cell to see the value.
P(X ≤ x, ν) for x from 0.0 to 30.9
| x | .0 | .1 | .2 | .3 | .4 | .5 | .6 | .7 | .8 | .9 |
|---|---|---|---|---|---|---|---|---|---|---|
| 0.0 | 0.0000 | 0.0002 | 0.0009 | 0.0024 | 0.0047 | 0.0079 | 0.0120 | 0.0170 | 0.0230 | 0.0298 |
| 1.0 | 0.0374 | 0.0459 | 0.0551 | 0.0651 | 0.0757 | 0.0869 | 0.0988 | 0.1111 | 0.1239 | 0.1372 |
| 2.0 | 0.1509 | 0.1649 | 0.1792 | 0.1937 | 0.2085 | 0.2235 | 0.2386 | 0.2539 | 0.2692 | 0.2846 |
| 3.0 | 0.3000 | 0.3154 | 0.3308 | 0.3462 | 0.3614 | 0.3766 | 0.3917 | 0.4066 | 0.4214 | 0.4361 |
| 4.0 | 0.4506 | 0.4649 | 0.4790 | 0.4929 | 0.5066 | 0.5201 | 0.5334 | 0.5464 | 0.5592 | 0.5718 |
| 5.0 | 0.5841 | 0.5962 | 0.6080 | 0.6196 | 0.6310 | 0.6421 | 0.6529 | 0.6635 | 0.6738 | 0.6839 |
| 6.0 | 0.6938 | 0.7034 | 0.7128 | 0.7219 | 0.7308 | 0.7394 | 0.7479 | 0.7561 | 0.7641 | 0.7718 |
| 7.0 | 0.7794 | 0.7867 | 0.7938 | 0.8007 | 0.8074 | 0.8140 | 0.8203 | 0.8264 | 0.8324 | 0.8382 |
| 8.0 | 0.8438 | 0.8492 | 0.8544 | 0.8595 | 0.8645 | 0.8693 | 0.8739 | 0.8784 | 0.8827 | 0.8869 |
| 9.0 | 0.8909 | 0.8949 | 0.8987 | 0.9023 | 0.9059 | 0.9093 | 0.9126 | 0.9158 | 0.9189 | 0.9219 |
| 10.0 | 0.9248 | 0.9275 | 0.9302 | 0.9328 | 0.9353 | 0.9378 | 0.9401 | 0.9423 | 0.9445 | 0.9466 |
| 11.0 | 0.9486 | 0.9506 | 0.9524 | 0.9543 | 0.9560 | 0.9577 | 0.9593 | 0.9609 | 0.9624 | 0.9638 |
| 12.0 | 0.9652 | 0.9666 | 0.9679 | 0.9691 | 0.9703 | 0.9715 | 0.9726 | 0.9736 | 0.9747 | 0.9757 |
| 13.0 | 0.9766 | 0.9775 | 0.9784 | 0.9793 | 0.9801 | 0.9809 | 0.9816 | 0.9824 | 0.9831 | 0.9837 |
| 14.0 | 0.9844 | 0.9850 | 0.9856 | 0.9862 | 0.9867 | 0.9873 | 0.9878 | 0.9883 | 0.9887 | 0.9892 |
| 15.0 | 0.9896 | 0.9901 | 0.9905 | 0.9908 | 0.9912 | 0.9916 | 0.9919 | 0.9922 | 0.9926 | 0.9929 |
| 16.0 | 0.9932 | 0.9934 | 0.9937 | 0.9940 | 0.9942 | 0.9944 | 0.9947 | 0.9949 | 0.9951 | 0.9953 |
| 17.0 | 0.9955 | 0.9957 | 0.9959 | 0.9960 | 0.9962 | 0.9964 | 0.9965 | 0.9967 | 0.9968 | 0.9969 |
| 18.0 | 0.9971 | 0.9972 | 0.9973 | 0.9974 | 0.9975 | 0.9976 | 0.9977 | 0.9978 | 0.9979 | 0.9980 |
| 19.0 | 0.9981 | 0.9982 | 0.9982 | 0.9983 | 0.9984 | 0.9984 | 0.9985 | 0.9986 | 0.9986 | 0.9987 |
| 20.0 | 0.9988 | 0.9988 | 0.9989 | 0.9989 | 0.9989 | 0.9990 | 0.9990 | 0.9991 | 0.9991 | 0.9992 |
| 21.0 | 0.9992 | 0.9992 | 0.9993 | 0.9993 | 0.9993 | 0.9993 | 0.9994 | 0.9994 | 0.9994 | 0.9995 |
| 22.0 | 0.9995 | 0.9995 | 0.9995 | 0.9995 | 0.9996 | 0.9996 | 0.9996 | 0.9996 | 0.9996 | 0.9996 |
| 23.0 | 0.9997 | 0.9997 | 0.9997 | 0.9997 | 0.9997 | 0.9997 | 0.9997 | 0.9998 | 0.9998 | 0.9998 |
| 24.0 | 0.9998 | 0.9998 | 0.9998 | 0.9998 | 0.9998 | 0.9998 | 0.9998 | 0.9998 | 0.9998 | 0.9999 |
| 25.0 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 |
| 26.0 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 | 0.9999 |
| 27.0 | 0.9999 | 0.9999 | 0.9999 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 |
| 28.0 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 |
| 29.0 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 |
| 30.0 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 | 1.0000 |
How to read the table: each cell shows the density f(x, ν). The χ² distribution is defined for x ≥ 0. As ν increases, the curve becomes more symmetric and shifts to the right.
Click a cell to see the value.
f(x, ν) for x from 0.0 to 30.9
| x | .0 | .1 | .2 | .3 | .4 | .5 | .6 | .7 | .8 | .9 |
|---|---|---|---|---|---|---|---|---|---|---|
| 0.0 | 0.0000 | 0.0040 | 0.0108 | 0.0188 | 0.0275 | 0.0366 | 0.0458 | 0.0549 | 0.0638 | 0.0724 |
| 1.0 | 0.0807 | 0.0885 | 0.0959 | 0.1029 | 0.1094 | 0.1154 | 0.1209 | 0.1260 | 0.1306 | 0.1347 |
| 2.0 | 0.1384 | 0.1416 | 0.1444 | 0.1469 | 0.1489 | 0.1506 | 0.1519 | 0.1529 | 0.1536 | 0.1540 |
| 3.0 | 0.1542 | 0.1541 | 0.1537 | 0.1531 | 0.1523 | 0.1513 | 0.1501 | 0.1488 | 0.1473 | 0.1457 |
| 4.0 | 0.1440 | 0.1421 | 0.1402 | 0.1381 | 0.1360 | 0.1338 | 0.1315 | 0.1292 | 0.1269 | 0.1245 |
| 5.0 | 0.1220 | 0.1196 | 0.1171 | 0.1146 | 0.1121 | 0.1097 | 0.1072 | 0.1047 | 0.1022 | 0.0997 |
| 6.0 | 0.0973 | 0.0949 | 0.0925 | 0.0901 | 0.0878 | 0.0854 | 0.0832 | 0.0809 | 0.0787 | 0.0765 |
| 7.0 | 0.0744 | 0.0723 | 0.0702 | 0.0682 | 0.0662 | 0.0642 | 0.0623 | 0.0605 | 0.0586 | 0.0569 |
| 8.0 | 0.0551 | 0.0534 | 0.0517 | 0.0501 | 0.0485 | 0.0470 | 0.0455 | 0.0440 | 0.0426 | 0.0412 |
| 9.0 | 0.0399 | 0.0386 | 0.0373 | 0.0361 | 0.0349 | 0.0337 | 0.0326 | 0.0314 | 0.0304 | 0.0293 |
| 10.0 | 0.0283 | 0.0274 | 0.0264 | 0.0255 | 0.0246 | 0.0237 | 0.0229 | 0.0221 | 0.0213 | 0.0206 |
| 11.0 | 0.0198 | 0.0191 | 0.0184 | 0.0178 | 0.0171 | 0.0165 | 0.0159 | 0.0153 | 0.0148 | 0.0142 |
| 12.0 | 0.0137 | 0.0132 | 0.0127 | 0.0122 | 0.0118 | 0.0113 | 0.0109 | 0.0105 | 0.0101 | 0.0097 |
| 13.0 | 0.0094 | 0.0090 | 0.0087 | 0.0083 | 0.0080 | 0.0077 | 0.0074 | 0.0071 | 0.0069 | 0.0066 |
| 14.0 | 0.0064 | 0.0061 | 0.0059 | 0.0056 | 0.0054 | 0.0052 | 0.0050 | 0.0048 | 0.0046 | 0.0044 |
| 15.0 | 0.0043 | 0.0041 | 0.0039 | 0.0038 | 0.0036 | 0.0035 | 0.0034 | 0.0032 | 0.0031 | 0.0030 |
| 16.0 | 0.0029 | 0.0027 | 0.0026 | 0.0025 | 0.0024 | 0.0023 | 0.0022 | 0.0021 | 0.0021 | 0.0020 |
| 17.0 | 0.0019 | 0.0018 | 0.0017 | 0.0017 | 0.0016 | 0.0015 | 0.0015 | 0.0014 | 0.0014 | 0.0013 |
| 18.0 | 0.0013 | 0.0012 | 0.0012 | 0.0011 | 0.0011 | 0.0010 | 0.0010 | 0.0009 | 0.0009 | 0.0009 |
| 19.0 | 0.0008 | 0.0008 | 0.0008 | 0.0007 | 0.0007 | 0.0007 | 0.0006 | 0.0006 | 0.0006 | 0.0006 |
| 20.0 | 0.0005 | 0.0005 | 0.0005 | 0.0005 | 0.0005 | 0.0004 | 0.0004 | 0.0004 | 0.0004 | 0.0004 |
| 21.0 | 0.0004 | 0.0003 | 0.0003 | 0.0003 | 0.0003 | 0.0003 | 0.0003 | 0.0003 | 0.0002 | 0.0002 |
| 22.0 | 0.0002 | 0.0002 | 0.0002 | 0.0002 | 0.0002 | 0.0002 | 0.0002 | 0.0002 | 0.0002 | 0.0002 |
| 23.0 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 |
| 24.0 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 |
| 25.0 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0001 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 |
| 26.0 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 |
| 27.0 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 |
| 28.0 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 |
| 29.0 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 |
| 30.0 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 | 0.0000 |
How to use these tables
Chi-Square Distribution
If Z₁, Z₂, …, Zᵥ are independent standard normal variables, then X = Z₁² + … + Zᵥ² follows a chi-square distribution with ν degrees of freedom. Its density function is:
\( f(x,\nu) = \dfrac{x^{\nu/2-1}\,e^{-x/2}}{2^{\nu/2}\,\Gamma(\nu/2)}, \quad x \geq 0 \)
The mean is ν and the variance is 2ν.
Critical values table
Shows the quantiles χ²(p, ν) such that P(X ≤ χ²) = p. For a test at significance level α (right tail) with ν degrees of freedom, use the column p = 1 − α.
- Example: test at 5%, ν = 5 → p = 0.95 → χ² = 11.070.
- Columns with p < 0.5 correspond to the left tail (small values of χ²).
Main uses
- Goodness-of-fit test
- Test of independence in contingency tables
- Variance estimation and confidence intervals for σ²
- Homogeneity tests