Celestra Grey vs Grey Green

How close are they?

ΔE 17.2, loose: different enough that you should pick on purpose. Grey Green is a little darker, warmer than Celestra Grey.

Can I use Grey Green instead of Celestra Grey?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Grey Green is a little darker, warmer than Celestra Grey.

Can I use Celestra Grey instead of Grey Green?

The same difference applies the other way round: Celestra Grey is a little lighter, 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.