Purple Tone vs Blue Wash

How close are they?

ΔE 52.1, loose: different enough that you should pick on purpose. Blue Wash is noticeably lighter, more muted, cooler than Purple Tone.

Can I use Blue Wash instead of Purple Tone?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 52). Blue Wash is noticeably lighter, more muted, cooler than Purple Tone.

Can I use Purple Tone instead of Blue Wash?

The same difference applies the other way round: Purple Tone is noticeably darker, more saturated, 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.