ΔE 22.5, loose: different enough that you should pick on purpose. Olive Green is much more muted, warmer than Savage Green.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 23). Olive Green is much more muted, warmer than Savage Green.
The same difference applies the other way round: Savage Green is much more saturated, cooler.
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 Savage Green on the colour wheel See Olive Green on the colour wheel
All matches: Savage Green equivalents · Olive Green equivalents