ΔE 17.5, loose: different enough that you should pick on purpose. Warm Grey is a little darker, more muted than Tanker Grey.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Warm Grey is a little darker, more muted than Tanker Grey.
The same difference applies the other way round: Tanker Grey is a little lighter, 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.
See Tanker Grey on the colour wheel See Warm Grey on the colour wheel
All matches: Tanker Grey equivalents · Warm Grey equivalents