ΔE 6.5, close: similar, with a visible difference side by side. IDF/IAF Green is a little darker than Cockpit Green (IJN).
Usually, if you are not matching paint already on the model. Close match (ΔE 6). IDF/IAF Green is a little darker than Cockpit Green (IJN).
The same difference applies the other way round: Cockpit Green (IJN) is a little lighter.
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 Cockpit Green (IJN) on the colour wheel See IDF/IAF Green on the colour wheel
All matches: Cockpit Green (IJN) equivalents · IDF/IAF Green equivalents