ΔE 7.8, close: similar, with a visible difference side by side. Gray FS26440 is a little lighter than Combat Fatigues.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). Gray FS26440 is a little lighter than Combat Fatigues.
The same difference applies the other way round: Combat Fatigues is a little darker.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Combat Fatigues on the colour wheel See Gray FS26440 on the colour wheel
All matches: Combat Fatigues equivalents · Gray FS26440 equivalents