ΔE 8.4, close: similar, with a visible difference side by side. Green Brown is more saturated than Gengis Khaki.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). Green Brown is more saturated than Gengis Khaki.
The same difference applies the other way round: Gengis Khaki is more muted.
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 Gengis Khaki on the colour wheel See Green Brown on the colour wheel
All matches: Gengis Khaki equivalents · Green Brown equivalents