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F-table (critical values for ANOVA and regression)

Critical values of the F distribution at the two standard significance levels, plus an exact lookup for any df1/df2 pair — no more interpolating between printed columns.

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Exact F lookup

Any df1/df2 pair and α — exact critical value and p-value.

Critical values of F at α = .05

Numerator df (df1, between groups) across the top; denominator df (df2, within groups / error) down the side.

df2 \ df1123456781012152030
1161.4199.5215.7224.6230.2234.0236.8238.9241.9243.9245.9248.0250.1
218.5119.0019.1619.2519.3019.3319.3519.3719.4019.4119.4319.4519.46
310.139.559.289.129.018.948.898.858.798.748.708.668.62
47.716.946.596.396.266.166.096.045.965.915.865.805.75
56.615.795.415.195.054.954.884.824.744.684.624.564.50
65.995.144.764.534.394.284.214.154.064.003.943.873.81
75.594.744.354.123.973.873.793.733.643.573.513.443.38
85.324.464.073.843.693.583.503.443.353.283.223.153.08
95.124.263.863.633.483.373.293.233.143.073.012.942.86
104.964.103.713.483.333.223.143.072.982.912.852.772.70
124.753.893.493.263.113.002.912.852.752.692.622.542.47
144.603.743.343.112.962.852.762.702.602.532.462.392.31
164.493.633.243.012.852.742.662.592.492.422.352.282.19
184.413.553.162.932.772.662.582.512.412.342.272.192.11
204.353.493.102.872.712.602.512.452.352.282.202.122.04
254.243.392.992.762.602.492.402.342.242.162.092.011.92
304.173.322.922.692.532.422.332.272.162.092.011.931.84
404.083.232.842.612.452.342.252.182.082.001.921.841.74
604.003.152.762.532.372.252.172.101.991.921.841.751.65
1203.923.072.682.452.292.182.092.021.911.831.751.661.55

Reject H0 when F exceeds the table value. For a one-way ANOVA with k groups and N total participants: df1 = k − 1, df2 = N − k.

Critical values of F at α = .01

Numerator df (df1, between groups) across the top; denominator df (df2, within groups / error) down the side.

df2 \ df1123456781012152030
14052.24999.55403.45624.65763.65859.05928.45981.16055.86106.36157.36208.76260.6
298.5099.0099.1799.2599.3099.3399.3699.3799.4099.4299.4399.4599.47
334.1230.8229.4628.7128.2427.9127.6727.4927.2327.0526.8726.6926.50
421.2018.0016.6915.9815.5215.2114.9814.8014.5514.3714.2014.0213.84
516.2613.2712.0611.3910.9710.6710.4610.2910.059.899.729.559.38
613.7510.929.789.158.758.478.268.107.877.727.567.407.23
712.259.558.457.857.467.196.996.846.626.476.316.165.99
811.268.657.597.016.636.376.186.035.815.675.525.365.20
910.568.026.996.426.065.805.615.475.265.114.964.814.65
1010.047.566.555.995.645.395.205.064.854.714.564.414.25
129.336.935.955.415.064.824.644.504.304.164.013.863.70
148.866.515.565.044.694.464.284.143.943.803.663.513.35
168.536.235.294.774.444.204.033.893.693.553.413.263.10
188.296.015.094.584.254.013.843.713.513.373.233.082.92
208.105.854.944.434.103.873.703.563.373.233.092.942.78
257.775.574.684.183.853.633.463.323.132.992.852.702.54
307.565.394.514.023.703.473.303.172.982.842.702.552.39
407.315.184.313.833.513.293.122.992.802.662.522.372.20
607.084.984.133.653.343.122.952.822.632.502.352.202.03
1206.854.793.953.483.172.962.792.662.472.342.192.031.86

Reject H0 when F exceeds the table value. For a one-way ANOVA with k groups and N total participants: df1 = k − 1, df2 = N − k.

How to read the table

An F statistic is a ratio of variances, so it carries TWO degrees of freedom: the numerator df1 (across the top) and the denominator df2 (down the side). Find your α table, then the intersection. Example: a one-way ANOVA with 3 groups of 20 has df1 = 3 − 1 = 2 and df2 = 60 − 3 = 57; at α = .05 the critical value is about 3.16, so F(2, 57) = 4.4 is significant.

In regression, the overall model F uses df1 = number of predictors and df2 = n − predictors − 1. In ANOVA the same logic extends to each effect in a factorial design — each has its own df1 against the common error df2.

A significant F in an ANOVA with 3+ groups says only that SOME difference exists. Follow up with planned contrasts or post-hoc tests to find where, and report an effect size (η² or ω²) alongside.

Frequently asked questions

Which df is the numerator and which is the denominator?
Numerator (df1) belongs to the effect: groups − 1 in a one-way ANOVA, or the number of predictors in a regression F. Denominator (df2) belongs to the error term: N − k for one-way ANOVA, n − p − 1 in regression. Reporting convention: F(df1, df2) = value.
Why is F always one-tailed?
F is a ratio of squared quantities, so any group difference — in either direction — inflates it above 1. All the evidence against H0 collects in the upper tail; that is the only tail tested.
My exact df2 is not printed — which row do I use?
The exact lookup at the top takes any df pair. On paper, use the next SMALLER df2 (a slightly larger critical value, so the choice is conservative).

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