Caramel Brown vs UK Light Stone

How close are they?

ΔE 15.3, loose: different enough that you should pick on purpose. UK Light Stone is noticeably lighter, more saturated, cooler than Caramel Brown.

Can I use UK Light Stone instead of Caramel Brown?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). UK Light Stone is noticeably lighter, more saturated, cooler than Caramel Brown.

Can I use Caramel Brown instead of UK Light Stone?

The same difference applies the other way round: Caramel Brown is noticeably darker, 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.