t, Chi-Square and F Distributions
t-Distribution Probability Table: P(T > t)
The area to the right of t for Student's t distribution: turn a t-statistic into a p-value directly.
- t = 0 to 5
- df 1 to ∞
- p-value calculator
t Probability Table
Rows: t · Columns: degrees of freedom · Cells: upper-tail area P(T > t). Double it for a two-tailed p-value.
| Degrees of freedom (df) → t ↓ | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 12 | 15 | 20 | 25 | 30 | 40 | 60 | 120 | ∞ |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0.0 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 | 0.5000 |
| 0.1 | 0.4683 | 0.4647 | 0.4633 | 0.4626 | 0.4621 | 0.4618 | 0.4616 | 0.4614 | 0.4613 | 0.4612 | 0.4610 | 0.4608 | 0.4607 | 0.4606 | 0.4605 | 0.4604 | 0.4603 | 0.4603 | 0.4602 |
| 0.2 | 0.4372 | 0.4300 | 0.4271 | 0.4256 | 0.4247 | 0.4240 | 0.4236 | 0.4232 | 0.4230 | 0.4227 | 0.4224 | 0.4221 | 0.4218 | 0.4215 | 0.4214 | 0.4212 | 0.4211 | 0.4209 | 0.4207 |
| 0.3 | 0.4072 | 0.3962 | 0.3919 | 0.3896 | 0.3881 | 0.3871 | 0.3864 | 0.3859 | 0.3855 | 0.3852 | 0.3847 | 0.3841 | 0.3836 | 0.3833 | 0.3831 | 0.3829 | 0.3826 | 0.3823 | 0.3821 |
| 0.4 | 0.3789 | 0.3639 | 0.3580 | 0.3548 | 0.3528 | 0.3515 | 0.3505 | 0.3498 | 0.3492 | 0.3488 | 0.3481 | 0.3474 | 0.3467 | 0.3463 | 0.3460 | 0.3456 | 0.3453 | 0.3449 | 0.3446 |
| 0.5 | 0.3524 | 0.3333 | 0.3257 | 0.3217 | 0.3191 | 0.3174 | 0.3162 | 0.3153 | 0.3145 | 0.3139 | 0.3131 | 0.3122 | 0.3113 | 0.3107 | 0.3104 | 0.3099 | 0.3095 | 0.3090 | 0.3085 |
| 0.6 | 0.3280 | 0.3047 | 0.2954 | 0.2904 | 0.2873 | 0.2852 | 0.2837 | 0.2826 | 0.2817 | 0.2809 | 0.2798 | 0.2787 | 0.2776 | 0.2770 | 0.2765 | 0.2759 | 0.2754 | 0.2748 | 0.2743 |
| 0.7 | 0.3056 | 0.2782 | 0.2672 | 0.2613 | 0.2576 | 0.2551 | 0.2533 | 0.2519 | 0.2508 | 0.2499 | 0.2486 | 0.2473 | 0.2460 | 0.2452 | 0.2447 | 0.2440 | 0.2433 | 0.2426 | 0.2420 |
| 0.8 | 0.2852 | 0.2538 | 0.2411 | 0.2343 | 0.2300 | 0.2271 | 0.2250 | 0.2234 | 0.2222 | 0.2212 | 0.2196 | 0.2181 | 0.2166 | 0.2156 | 0.2150 | 0.2142 | 0.2134 | 0.2126 | 0.2119 |
| 0.9 | 0.2667 | 0.2316 | 0.2172 | 0.2095 | 0.2047 | 0.2014 | 0.1990 | 0.1972 | 0.1958 | 0.1946 | 0.1929 | 0.1912 | 0.1894 | 0.1884 | 0.1876 | 0.1868 | 0.1859 | 0.1850 | 0.1841 |
| 1.0 | 0.2500 | 0.2113 | 0.1955 | 0.1870 | 0.1816 | 0.1780 | 0.1753 | 0.1733 | 0.1717 | 0.1704 | 0.1685 | 0.1666 | 0.1646 | 0.1634 | 0.1627 | 0.1617 | 0.1607 | 0.1597 | 0.1587 |
| 1.1 | 0.2349 | 0.1930 | 0.1758 | 0.1665 | 0.1607 | 0.1567 | 0.1539 | 0.1517 | 0.1499 | 0.1486 | 0.1465 | 0.1443 | 0.1422 | 0.1409 | 0.1400 | 0.1390 | 0.1379 | 0.1368 | 0.1357 |
| 1.2 | 0.2211 | 0.1765 | 0.1581 | 0.1482 | 0.1419 | 0.1377 | 0.1346 | 0.1322 | 0.1304 | 0.1289 | 0.1266 | 0.1244 | 0.1221 | 0.1207 | 0.1198 | 0.1186 | 0.1174 | 0.1163 | 0.1151 |
| 1.3 | 0.2087 | 0.1616 | 0.1422 | 0.1317 | 0.1252 | 0.1207 | 0.1174 | 0.1149 | 0.1130 | 0.1114 | 0.1090 | 0.1066 | 0.1042 | 0.1027 | 0.1018 | 0.1005 | 0.0993 | 0.0980 | 0.0968 |
| 1.4 | 0.1974 | 0.1482 | 0.1280 | 0.1171 | 0.1102 | 0.1055 | 0.1021 | 0.0995 | 0.0975 | 0.0959 | 0.0934 | 0.0909 | 0.0884 | 0.0869 | 0.0859 | 0.0846 | 0.0833 | 0.0820 | 0.0808 |
| 1.5 | 0.1872 | 0.1362 | 0.1153 | 0.1040 | 0.0970 | 0.0921 | 0.0886 | 0.0860 | 0.0839 | 0.0823 | 0.0797 | 0.0772 | 0.0746 | 0.0731 | 0.0720 | 0.0707 | 0.0694 | 0.0681 | 0.0668 |
| 1.6 | 0.1778 | 0.1254 | 0.1040 | 0.0924 | 0.0852 | 0.0804 | 0.0768 | 0.0741 | 0.0720 | 0.0703 | 0.0678 | 0.0652 | 0.0626 | 0.0611 | 0.0600 | 0.0587 | 0.0574 | 0.0561 | 0.0548 |
| 1.7 | 0.1693 | 0.1156 | 0.0938 | 0.0822 | 0.0749 | 0.0700 | 0.0665 | 0.0638 | 0.0617 | 0.0600 | 0.0574 | 0.0549 | 0.0523 | 0.0508 | 0.0497 | 0.0484 | 0.0472 | 0.0459 | 0.0446 |
| 1.8 | 0.1614 | 0.1068 | 0.0848 | 0.0731 | 0.0659 | 0.0610 | 0.0574 | 0.0548 | 0.0527 | 0.0510 | 0.0485 | 0.0460 | 0.0435 | 0.0420 | 0.0410 | 0.0397 | 0.0384 | 0.0372 | 0.0359 |
| 1.9 | 0.1542 | 0.0989 | 0.0768 | 0.0651 | 0.0579 | 0.0531 | 0.0496 | 0.0470 | 0.0449 | 0.0433 | 0.0409 | 0.0384 | 0.0360 | 0.0345 | 0.0335 | 0.0323 | 0.0311 | 0.0299 | 0.0287 |
| 2.0 | 0.1476 | 0.0918 | 0.0697 | 0.0581 | 0.0510 | 0.0462 | 0.0428 | 0.0403 | 0.0383 | 0.0367 | 0.0343 | 0.0320 | 0.0296 | 0.0282 | 0.0273 | 0.0262 | 0.0250 | 0.0239 | 0.0228 |
| 2.1 | 0.1415 | 0.0853 | 0.0633 | 0.0518 | 0.0449 | 0.0402 | 0.0369 | 0.0345 | 0.0326 | 0.0310 | 0.0288 | 0.0265 | 0.0243 | 0.0230 | 0.0221 | 0.0210 | 0.0200 | 0.0189 | 0.0179 |
| 2.2 | 0.1358 | 0.0794 | 0.0576 | 0.0463 | 0.0395 | 0.0351 | 0.0319 | 0.0295 | 0.0277 | 0.0262 | 0.0241 | 0.0219 | 0.0199 | 0.0186 | 0.0178 | 0.0168 | 0.0158 | 0.0149 | 0.0139 |
| 2.3 | 0.1305 | 0.0741 | 0.0525 | 0.0415 | 0.0349 | 0.0306 | 0.0275 | 0.0252 | 0.0235 | 0.0221 | 0.0201 | 0.0181 | 0.0162 | 0.0150 | 0.0143 | 0.0134 | 0.0125 | 0.0116 | 0.0107 |
| 2.4 | 0.1257 | 0.0692 | 0.0479 | 0.0372 | 0.0308 | 0.0266 | 0.0237 | 0.0216 | 0.0199 | 0.0187 | 0.0168 | 0.0149 | 0.0131 | 0.0121 | 0.0114 | 0.0106 | 0.0098 | 0.0090 | 0.0082 |
| 2.5 | 0.1211 | 0.0648 | 0.0439 | 0.0334 | 0.0272 | 0.0233 | 0.0205 | 0.0185 | 0.0169 | 0.0157 | 0.0140 | 0.0123 | 0.0106 | 0.0097 | 0.0091 | 0.0083 | 0.0076 | 0.0069 | 0.0062 |
| 2.6 | 0.1169 | 0.0608 | 0.0402 | 0.0300 | 0.0241 | 0.0203 | 0.0177 | 0.0158 | 0.0144 | 0.0132 | 0.0116 | 0.0100 | 0.0086 | 0.0077 | 0.0072 | 0.0065 | 0.0059 | 0.0052 | 0.0047 |
| 2.7 | 0.1129 | 0.0571 | 0.0369 | 0.0270 | 0.0214 | 0.0178 | 0.0153 | 0.0135 | 0.0122 | 0.0112 | 0.0097 | 0.0082 | 0.0069 | 0.0061 | 0.0056 | 0.0051 | 0.0045 | 0.0040 | 0.0035 |
| 2.8 | 0.1092 | 0.0537 | 0.0339 | 0.0244 | 0.0190 | 0.0156 | 0.0133 | 0.0116 | 0.0104 | 0.0094 | 0.0080 | 0.0067 | 0.0055 | 0.0049 | 0.0044 | 0.0039 | 0.0034 | 0.0030 | 0.0026 |
| 2.9 | 0.1057 | 0.0506 | 0.0313 | 0.0221 | 0.0169 | 0.0137 | 0.0115 | 0.0099 | 0.0088 | 0.0079 | 0.0067 | 0.0055 | 0.0044 | 0.0038 | 0.0035 | 0.0030 | 0.0026 | 0.0022 | 0.0019 |
| 3.0 | 0.1024 | 0.0477 | 0.0288 | 0.0200 | 0.0150 | 0.0120 | 0.0100 | 0.0085 | 0.0075 | 0.0067 | 0.0055 | 0.0045 | 0.0035 | 0.0030 | 0.0027 | 0.0023 | 0.0020 | 0.0016 | 0.0013 |
| 3.1 | 0.0993 | 0.0451 | 0.0266 | 0.0181 | 0.0134 | 0.0106 | 0.0087 | 0.0073 | 0.0064 | 0.0056 | 0.0046 | 0.0037 | 0.0028 | 0.0024 | 0.0021 | 0.0018 | 0.0015 | 0.0012 | 0.0010 |
| 3.2 | 0.0964 | 0.0427 | 0.0247 | 0.0165 | 0.0120 | 0.0093 | 0.0075 | 0.0063 | 0.0054 | 0.0047 | 0.0038 | 0.0030 | 0.0022 | 0.0019 | 0.0016 | 0.0013 | 0.0011 | 0.0009 | 0.0007 |
| 3.3 | 0.0937 | 0.0404 | 0.0229 | 0.0150 | 0.0107 | 0.0082 | 0.0066 | 0.0054 | 0.0046 | 0.0040 | 0.0032 | 0.0024 | 0.0018 | 0.0015 | 0.0012 | 0.0010 | 0.0008 | 0.0006 | 0.0005 |
| 3.4 | 0.0911 | 0.0383 | 0.0212 | 0.0136 | 0.0096 | 0.0072 | 0.0057 | 0.0047 | 0.0039 | 0.0034 | 0.0026 | 0.0020 | 0.0014 | 0.0011 | 0.0010 | 0.0008 | 0.0006 | 0.0005 | 0.0003 |
| 3.5 | 0.0886 | 0.0364 | 0.0197 | 0.0124 | 0.0086 | 0.0064 | 0.0050 | 0.0040 | 0.0034 | 0.0029 | 0.0022 | 0.0016 | 0.0011 | 0.0009 | 0.0007 | 0.0006 | 0.0004 | 0.0003 | 0.0002 |
| 3.6 | 0.0862 | 0.0346 | 0.0184 | 0.0114 | 0.0078 | 0.0057 | 0.0044 | 0.0035 | 0.0029 | 0.0024 | 0.0018 | 0.0013 | 0.0009 | 0.0007 | 0.0006 | 0.0004 | 0.0003 | 0.0002 | 0.0002 |
| 3.7 | 0.0840 | 0.0330 | 0.0171 | 0.0104 | 0.0070 | 0.0050 | 0.0038 | 0.0030 | 0.0025 | 0.0021 | 0.0015 | 0.0011 | 0.0007 | 0.0005 | 0.0004 | 0.0003 | 0.0002 | 0.0002 | 0.0001 |
| 3.8 | 0.0819 | 0.0314 | 0.0160 | 0.0096 | 0.0063 | 0.0045 | 0.0034 | 0.0026 | 0.0021 | 0.0017 | 0.0013 | 0.0009 | 0.0006 | 0.0004 | 0.0003 | 0.0002 | 0.0002 | 0.0001 | 0.0001 |
| 3.9 | 0.0799 | 0.0299 | 0.0150 | 0.0088 | 0.0057 | 0.0040 | 0.0029 | 0.0023 | 0.0018 | 0.0015 | 0.0011 | 0.0007 | 0.0004 | 0.0003 | 0.0003 | 0.0002 | 0.0001 | 0.0001 | 0+ |
| 4.0 | 0.0780 | 0.0286 | 0.0140 | 0.0081 | 0.0052 | 0.0036 | 0.0026 | 0.0020 | 0.0016 | 0.0013 | 0.0009 | 0.0006 | 0.0004 | 0.0002 | 0.0002 | 0.0001 | 0.0001 | 0.0001 | 0+ |
| 4.5 | 0.0696 | 0.0230 | 0.0102 | 0.0054 | 0.0032 | 0.0021 | 0.0014 | 0.0010 | 0.0007 | 0.0006 | 0.0004 | 0.0002 | 0.0001 | 0.0001 | 0+ | 0+ | 0+ | 0+ | 0+ |
| 5.0 | 0.0628 | 0.0189 | 0.0077 | 0.0037 | 0.0021 | 0.0012 | 0.0008 | 0.0005 | 0.0004 | 0.0003 | 0.0002 | 0.0001 | 0+ | 0+ | 0+ | 0+ | 0+ | 0+ | 0+ |
Tip: click any value to highlight its row and column.
How to read this table
- Find the row for your t-statistic (use |t| for a two-tailed test) and the column for df.
- The cell is the one-tailed p-value P(T > t).
- For a two-tailed p-value, double it.
Worked example
A paired t-test on 16 patients gives t = 2.1 with df = 15. Row 2.1, column 15 gives 0.0265, so the two-tailed p-value is 2 × 0.0265 = 0.0530.
Click the underlined links to highlight the value in the table.
Calculator
For values between the rows and columns of the table. Results update as you type.
Formula and how the values were computed
Each cell is the upper-tail probability of Student's t with the given df, computed in double precision and rounded to four decimals. The ∞ column is the standard normal distribution.
Frequently asked questions
How is this different from the t table?
The Student's t table lists critical values for fixed α. This table goes the other way, from a t-statistic to its p-value.