Jungle Green vs Light Green

How close are they?

ΔE 25.1, loose: different enough that you should pick on purpose. Light Green is noticeably lighter, much more saturated than Jungle Green.

Can I use Light Green instead of Jungle Green?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 25). Light Green is noticeably lighter, much more saturated than Jungle Green.

Can I use Jungle Green instead of Light Green?

The same difference applies the other way round: Jungle Green is noticeably darker, much 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.