F-Distribution Table

Critical values for the F-distribution at significance levels α = 0.05 and α = 0.01, organized by numerator degrees of freedom (df₁) and denominator degrees of freedom (df₂). Use this table for ANOVA tests, variance ratio tests, and regression significance testing.

What is the F-Distribution?

The F-distribution is a right-skewed distribution that arises when comparing two independent chi-square variables divided by their degrees of freedom. It is defined by two parameters: df₁ (numerator) and df₂ (denominator).

  • F-statistic: F = (s₁² / σ₁²) / (s₂² / σ₂²), where s² are sample variances.
  • One-way ANOVA: F = MSbetween / MSwithin, with df₁ = k − 1 and df₂ = N − k.
  • Regression: F tests whether the overall regression model explains a significant portion of variance.
  • Always right-tailed: reject H₀ when F calculated exceeds the critical value.

Critical F-Values at α = 0.05

Each cell shows the critical value F0.05, df₁, df₂. Columns are numerator degrees of freedom (df₁); rows are denominator degrees of freedom (df₂).

df₂ \ df₁123456781012152030
1161.45199.50215.71224.58230.16233.99236.77238.88241.88243.91245.95248.01250.10254.32
218.5119.0019.1619.2519.3019.3319.3519.3719.4019.4119.4319.4519.4619.50
310.139.559.289.129.018.948.898.858.798.748.708.668.628.53
47.716.946.596.396.266.166.096.045.965.915.865.805.755.63
56.615.795.415.195.054.954.884.824.744.684.624.564.504.37
65.995.144.764.534.394.284.214.154.064.003.943.873.813.67
75.594.744.354.123.973.873.793.733.643.573.513.443.383.23
85.324.464.073.843.693.583.503.443.353.283.223.153.082.93
95.124.263.863.633.483.373.293.233.143.073.012.942.862.71
104.964.103.713.483.333.223.143.072.982.912.852.772.702.54
114.843.983.593.363.203.093.012.952.852.792.722.652.572.40
124.753.893.493.263.113.002.912.852.752.692.622.542.472.30
134.673.813.413.183.032.922.832.772.672.602.532.462.382.21
144.603.743.343.112.962.852.762.702.602.532.462.392.312.13
154.543.683.293.062.902.792.712.642.542.482.402.332.252.07
164.493.633.243.012.852.742.662.592.492.422.352.282.192.01
174.453.593.202.962.812.702.612.552.452.382.312.232.151.96
184.413.553.162.932.772.662.582.512.412.342.272.192.111.92
194.383.523.132.902.742.632.542.482.382.312.232.162.071.88
204.353.493.102.872.712.602.512.452.352.282.202.122.041.84
254.243.392.992.762.602.492.402.342.242.162.092.011.921.71
304.173.322.922.692.532.422.332.272.162.092.011.931.841.62
404.083.232.842.612.452.342.252.182.082.001.921.841.741.51
604.003.152.762.532.372.252.172.101.991.921.841.751.651.39
1203.923.072.682.452.292.182.092.021.911.831.751.661.551.25
3.843.002.612.372.222.102.011.941.831.751.671.571.461.00

Critical F-Values at α = 0.01

Use this table for more stringent hypothesis tests. Same structure as above: columns are df₁ (numerator), rows are df₂ (denominator).

df₂ \ df₁123456781012152030
140525000540356255764585959285981605661066157620962616366
298.5099.0099.1799.2599.3099.3399.3699.3799.4099.4299.4399.4599.4799.50
334.1230.8229.4628.7128.2427.9127.6727.4927.2327.0526.8726.6926.5026.13
421.2018.0016.6915.9815.5215.2114.9814.8014.5514.3714.2014.0213.8413.46
516.2613.2712.0611.3910.9710.6710.4610.2910.059.899.729.559.389.02
613.7510.929.789.158.758.478.268.107.877.727.567.407.236.88
712.259.558.457.857.467.196.996.846.626.476.316.165.995.65
811.268.657.597.016.636.376.186.035.815.675.525.365.204.86
910.568.026.996.426.065.805.615.475.265.114.964.814.654.31
1010.047.566.555.995.645.395.205.064.854.714.564.414.253.91
119.657.216.225.675.325.074.894.744.544.404.254.103.943.60
129.336.935.955.415.064.824.644.504.304.164.013.863.703.36
139.076.705.745.214.864.624.444.304.103.963.823.663.513.17
148.866.515.565.044.694.464.284.143.943.803.663.513.353.00
158.686.365.424.894.564.324.144.003.803.673.523.373.212.87
168.536.235.294.774.444.204.033.893.693.553.413.263.102.75
178.406.115.184.674.344.103.933.793.593.463.313.163.002.65
188.296.015.094.584.254.013.843.713.513.373.233.082.922.57
198.185.935.014.504.173.943.773.633.433.303.153.002.842.49
208.105.854.944.434.103.873.703.563.373.233.092.942.782.42
257.775.574.684.183.853.633.463.323.132.992.852.702.542.17
307.565.394.514.023.703.473.303.172.982.842.702.552.392.01
407.315.184.313.833.513.293.122.992.802.662.522.372.201.80
607.084.984.133.653.343.122.952.822.632.502.352.202.031.60
1206.854.793.953.483.172.962.792.662.472.342.192.031.861.38
6.634.613.783.323.022.802.642.512.322.182.041.881.701.00

How to Use This Table

  • Calculate the F-statistic: F = (variance between groups) / (variance within groups), or F = s₁² / s₂² for a two-variance test.
  • Find df₁ and df₂: for one-way ANOVA, df₁ = k − 1 (groups minus 1) and df₂ = N − k (total observations minus groups).
  • Choose your significance level (α = 0.05 for the first table, α = 0.01 for the second).
  • Locate the critical value at the intersection of your df₁ column and df₂ row.
  • Compare: if F calculated > F critical, reject H₀. The F-test is always right-tailed.

References

See also