Calgar Blue vs Cerulean Blue, Chromium

How close are they?

ΔE 14.9, fair: the same colour family, but not a straight swap. Cerulean Blue, Chromium is noticeably lighter, more saturated than Calgar Blue.

Can I use Cerulean Blue, Chromium instead of Calgar Blue?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 15). Cerulean Blue, Chromium is noticeably lighter, more saturated than Calgar Blue.

Can I use Calgar Blue instead of Cerulean Blue, Chromium?

The same difference applies the other way round: Calgar Blue is noticeably darker, 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.