Appendix C
Critical Values of t
The values appearing on this page have been calculated via the built-in proprietary functions of Microsoft Excel.
Click one of the following links to go to the desired location within the table: df =
1-10, 11-20, 21-30, 31-40, 41-50, 51-60, 61-70, 71-85, >85
[At any place in the table, click "Top" to return to this location.] | Level of Significance for a Directional Test |
| 0.05 | 0.025 | 0.01 | 0.005 | 0.0005 |
| Level of Significance for a Non-directional Test |
| df | - | 0.05 | 0.02 | 0.01 | 0.001 |
| 1 | 6.31 | 12.71 | 31.82 | 63.66 | 636.58 |
| 2 | 2.92 | 4.30 | 6.96 | 9.92 | 31.60 |
| 3 | 2.35 | 3.18 | 4.54 | 5.84 | 12.92 |
| 4 | 2.13 | 2.78 | 3.75 | 4.60 | 8.61 |
| 5 | 2.02 | 2.57 | 3.36 | 4.03 | 6.87 |
| 6 | 1.94 | 2.45 | 3.14 | 3.71 | 5.96 |
| 7 | 1.89 | 2.36 | 3.00 | 3.50 | 5.41 |
| 8 | 1.86 | 2.31 | 2.90 | 3.36 | 5.04 |
| 9 | 1.83 | 2.26 | 2.82 | 3.25 | 4.78 |
| 10 | 1.81 | 2.23 | 2.76 | 3.17 | 4.59 |
Top | Level of Significance for a Directional Test |
| 0.05 | 0.025 | 0.01 | 0.005 | 0.0005 |
| Level of Significance for a Non-directional Test |
| df | 0.10 | 0.05 | 0.02 | 0.01 | 0.001 |
| 11 | 1.80 | 2.20 | 2.72 | 3.11 | 4.44 |
| 12 | 1.78 | 2.18 | 2.68 | 3.05 | 4.32 |
| 13 | 1.77 | 2.16 | 2.65 | 3.01 | 4.22 |
| 14 | 1.76 | 2.14 | 2.62 | 2.98 | 4.14 |
| 15 | 1.75 | 2.13 | 2.60 | 2.95 | 4.07 |
| 16 | 1.75 | 2.12 | 2.58 | 2.92 | 4.01 |
| 17 | 1.74 | 2.11 | 2.57 | 2.90 | 3.97 |
| 18 | 1.73 | 2.10 | 2.55 | 2.88 | 3.92 |
| 19 | 1.73 | 2.09 | 2.54 | 2.86 | 3.88 |
| 20 | 1.72 | 2.09 | 2.53 | 2.85 | 3.85 |
Top | Level of Significance for a Directional Test |
| 0.05 | 0.025 | 0.01 | 0.005 | 0.0005 |
| Level of Significance for a Non-directional Test |
| df | 0.10 | 0.05 | 0.02 | 0.01 | 0.001 |
| 21 | 1.72 | 2.08 | 2.52 | 2.83 | 3.82 |
| 22 | 1.72 | 2.07 | 2.51 | 2.82 | 3.79 |
| 23 | 1.71 | 2.07 | 2.50 | 2.81 | 3.77 |
| 24 | 1.71 | 2.06 | 2.49 | 2.80 | 3.75 |
| 25 | 1.71 | 2.06 | 2.49 | 2.79 | 3.73 |
| 26 | 1.71 | 2.06 | 2.48 | 2.78 | 3.71 |
| 27 | 1.70 | 2.05 | 2.47 | 2.77 | 3.69 |
| 28 | 1.70 | 2.05 | 2.47 | 2.76 | 3.67 |
| 29 | 1.70 | 2.05 | 2.46 | 2.76 | 3.66 |
| 30 | 1.70 | 2.04 | 2.46 | 2.75 | 3.65 |
Top | Level of Significance for a Directional Test |
| 0.05 | 0.025 | 0.01 | 0.005 | 0.0005 |
| Level of Significance for a Non-directional Test |
| df | 0.10 | 0.05 | 0.02 | 0.01 | 0.001 |
| 31 | 1.70 | 2.04 | 2.45 | 2.74 | 3.63 |
| 32 | 1.69 | 2.04 | 2.45 | 2.74 | 3.62 |
| 33 | 1.69 | 2.03 | 2.44 | 2.73 | 3.61 |
| 34 | 1.69 | 2.03 | 2.44 | 2.73 | 3.60 |
| 35 | 1.69 | 2.03 | 2.44 | 2.72 | 3.59 |
| 36 | 1.69 | 2.03 | 2.43 | 2.72 | 3.58 |
| 37 | 1.69 | 2.03 | 2.43 | 2.72 | 3.57 |
| 38 | 1.69 | 2.02 | 2.43 | 2.71 | 3.57 |
| 39 | 1.68 | 2.02 | 2.43 | 2.71 | 3.56 |
| 40 | 1.68 | 2.02 | 2.42 | 2.70 | 3.55 |
Top | Level of Significance for a Directional Test |
| 0.05 | 0.025 | 0.01 | 0.005 | 0.0005 |
| Level of Significance for a Non-directional Test |
| df | 0.10 | 0.05 | 0.02 | 0.01 | 0.001 |
| 41 | 1.68 | 2.02 | 2.42 | 2.70 | 3.54 |
| 42 | 1.68 | 2.02 | 2.42 | 2.70 | 3.54 |
| 43 | 1.68 | 2.02 | 2.42 | 2.70 | 3.53 |
| 44 | 1.68 | 2.02 | 2.41 | 2.69 | 3.53 |
| 45 | 1.68 | 2.01 | 2.41 | 2.69 | 3.52 |
| 46 | 1.68 | 2.01 | 2.41 | 2.69 | 3.51 |
| 47 | 1.68 | 2.01 | 2.41 | 2.68 | 3.51 |
| 48 | 1.68 | 2.01 | 2.41 | 2.68 | 3.50 |
| 49 | 1.68 | 2.01 | 2.40 | 2.68 | 3.50 |
| 50 | 1.68 | 2.01 | 2.40 | 2.68 | 3.50 |
Top | Level of Significance for a Directional Test |
| 0.05 | 0.025 | 0.01 | 0.005 | 0.0005 |
| Level of Significance for a Non-directional Test |
| df | 0.10 | 0.05 | 0.02 | 0.01 | 0.001 |
| 51 | 1.68 | 2.01 | 2.40 | 2.68 | 3.49 |
| 52 | 1.67 | 2.01 | 2.40 | 2.67 | 3.49 |
| 53 | 1.67 | 2.01 | 2.40 | 2.67 | 3.48 |
| 54 | 1.67 | 2.00 | 2.40 | 2.67 | 3.48 |
| 55 | 1.67 | 2.00 | 2.40 | 2.67 | 3.48 |
| 56 | 1.67 | 2.00 | 2.39 | 2.67 | 3.47 |
| 57 | 1.67 | 2.00 | 2.39 | 2.66 | 3.47 |
| 58 | 1.67 | 2.00 | 2.39 | 2.66 | 3.47 |
| 59 | 1.67 | 2.00 | 2.39 | 2.66 | 3.46 |
| 60 | 1.67 | 2.00 | 2.39 | 2.66 | 3.46 |
Top | Level of Significance for a Directional Test |
| 0.05 | 0.025 | 0.01 | 0.005 | 0.0005 |
| Level of Significance for a Non-directional Test |
| df | 0.10 | 0.05 | 0.02 | 0.01 | 0.001 |
| 61 | 1.67 | 2.00 | 2.39 | 2.66 | 3.46 |
| 62 | 1.67 | 2.00 | 2.39 | 2.66 | 3.45 |
| 63 | 1.67 | 2.00 | 2.39 | 2.66 | 3.45 |
| 64 | 1.67 | 2.00 | 2.39 | 2.65 | 3.45 |
| 65 | 1.67 | 2.00 | 2.39 | 2.65 | 3.45 |
| 66 | 1.67 | 2.00 | 2.38 | 2.65 | 3.44 |
| 67 | 1.67 | 2.00 | 2.38 | 2.65 | 3.44 |
| 68 | 1.67 | 2.00 | 2.38 | 2.65 | 3.44 |
| 69 | 1.67 | 1.99 | 2.38 | 2.65 | 3.44 |
| 70 | 1.67 | 1.99 | 2.38 | 2.65 | 3.43 |
Top | Level of Significance for a Directional Test |
| 0.05 | 0.025 | 0.01 | 0.005 | 0.0005 |
| Level of Significance for a Non-directional Test |
| df | 0.10 | 0.05 | 0.02 | 0.01 | 0.001 |
| 71 | 1.67 | 1.99 | 2.38 | 2.65 | 3.43 |
| 72 | 1.67 | 1.99 | 2.38 | 2.65 | 3.43 |
| 73 | 1.67 | 1.99 | 2.38 | 2.64 | 3.43 |
| 74 | 1.67 | 1.99 | 2.38 | 2.64 | 3.43 |
| 75 | 1.67 | 1.99 | 2.38 | 2.64 | 3.42 |
| 76 | 1.67 | 1.99 | 2.38 | 2.64 | 3.42 |
| 77 | 1.66 | 1.99 | 2.38 | 2.64 | 3.42 |
| 78 | 1.66 | 1.99 | 2.38 | 2.64 | 3.42 |
| 79 | 1.66 | 1.99 | 2.37 | 2.64 | 3.42 |
| 80 | 1.66 | 1.99 | 2.37 | 2.64 | 3.42 |
| 81 | 1.66 | 1.99 | 2.37 | 2.64 | 3.41 |
| 82 | 1.66 | 1.99 | 2.37 | 2.64 | 3.41 |
| 83 | 1.66 | 1.99 | 2.37 | 2.64 | 3.41 |
| 84 | 1.66 | 1.99 | 2.37 | 2.64 | 3.41 |
| 85 | 1.66 | 1.99 | 2.37 | 2.63 | 3.41 |
Top | Level of Significance for a Directional Test |
| 0.05 | 0.025 | 0.01 | 0.005 | 0.0005 |
| Level of Significance for a Non-directional Test |
| df | 0.10 | 0.05 | 0.02 | 0.01 | 0.001 |
| 90 | 1.66 | 1.99 | 2.37 | 2.63 | 3.40 |
| 100 | 1.66 | 1.98 | 2.36 | 2.63 | 3.39 |
| 120 | 1.66 | 1.98 | 2.36 | 2.62 | 3.37 |
| 140 | 1.66 | 1.98 | 2.35 | 2.61 | 3.36 |
| 160 | 1.65 | 1.97 | 2.35 | 2.61 | 3.35 |
| 200 | 1.65 | 1.97 | 2.35 | 2.60 | 3.34 |
| 220 | 1.65 | 1.97 | 2.34 | 2.60 | 3.34 |
Top