ΔE 15.2, loose: different enough that you should pick on purpose. Spring Green is noticeably darker, more muted, warmer than Savage Green.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Spring Green is noticeably darker, more muted, warmer than Savage Green.
The same difference applies the other way round: Savage Green is noticeably lighter, 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 Spring Green on the colour wheel
All matches: Savage Green equivalents · Spring Green equivalents