Grass Green vs Moot Green

How close are they?

ΔE 22.5, loose: different enough that you should pick on purpose. Moot Green is a little darker, much more saturated, cooler than Grass Green.

Can I use Moot Green instead of Grass Green?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 23). Moot Green is a little darker, much more saturated, cooler than Grass Green.

Can I use Grass Green instead of Moot Green?

The same difference applies the other way round: Grass Green is a little lighter, much more muted, 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.