ΔE 15.7, loose: different enough that you should pick on purpose. Flat Yellow is a little lighter, more muted, cooler than Tiger Brown.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Flat Yellow is a little lighter, more muted, cooler than Tiger Brown.
The same difference applies the other way round: Tiger Brown is a little 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.
See Tiger Brown on the colour wheel See Flat Yellow on the colour wheel
All matches: Tiger Brown equivalents · Flat Yellow equivalents