ΔE 7.1, close: similar, with a visible difference side by side. Clear Viridian is a little darker than Kroak Green. They are different kinds of paint: Citadel Kroak Green is a wash/shade and Reaper Clear Viridian is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Clear Viridian is a little darker than Kroak Green. They are different kinds of paint.
The same difference applies the other way round: Kroak Green is a little lighter.
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 Kroak Green on the colour wheel See Clear Viridian on the colour wheel
All matches: Kroak Green equivalents · Clear Viridian equivalents