Sun Bleach Yellow vs Light Yellow

How close are they?

ΔE 21.3, loose: different enough that you should pick on purpose. Light Yellow is a little lighter, much more saturated than Sun Bleach Yellow.

Can I use Light Yellow instead of Sun Bleach Yellow?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 21). Light Yellow is a little lighter, much more saturated than Sun Bleach Yellow.

Can I use Sun Bleach Yellow instead of Light Yellow?

The same difference applies the other way round: Sun Bleach Yellow is a little 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.