Matt Dry Blood vs Ink Red

How close are they?

ΔE 36.0, loose: different enough that you should pick on purpose. Ink Red is noticeably darker, much more saturated, cooler than Matt Dry Blood.

Can I use Ink Red instead of Matt Dry Blood?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 36). Ink Red is noticeably darker, much more saturated, cooler than Matt Dry Blood.

Can I use Matt Dry Blood instead of Ink Red?

The same difference applies the other way round: Matt Dry Blood is noticeably lighter, much more muted, warmer.

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.