Golfag Brown vs Burnt Umber Light

How close are they?

ΔE 21.4, loose: different enough that you should pick on purpose. Burnt Umber Light is noticeably darker, much more muted than Golfag Brown.

Can I use Burnt Umber Light instead of Golfag Brown?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 21). Burnt Umber Light is noticeably darker, much more muted than Golfag Brown.

Can I use Golfag Brown instead of Burnt Umber Light?

The same difference applies the other way round: Golfag Brown is noticeably lighter, much more saturated.

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.