ΔE 9.2, close: similar, with a visible difference side by side. Faded P.R.U. Blue is a little lighter, cooler than Gray Green (Luftwaffe).
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Faded P.R.U. Blue is a little lighter, cooler than Gray Green (Luftwaffe).
The same difference applies the other way round: Gray Green (Luftwaffe) is a little darker, warmer.
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 Gray Green (Luftwaffe) on the colour wheel See Faded P.R.U. Blue on the colour wheel
All matches: Gray Green (Luftwaffe) equivalents · Faded P.R.U. Blue equivalents