ΔE 7.7, close: similar, with a visible difference side by side. Nuclear White is a little lighter than Valhallan Blizzard. They are different kinds of paint: Citadel Valhallan Blizzard is a technical paint or medium and Green Stuff World Nuclear White is an opaque base/layer 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 8). Nuclear White is a little lighter than Valhallan Blizzard. They are different kinds of paint.
The same difference applies the other way round: Valhallan Blizzard is a little darker.
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 Valhallan Blizzard on the colour wheel See Nuclear White on the colour wheel
All matches: Valhallan Blizzard equivalents · Nuclear White equivalents