ΔE 6.1, close: similar, with a visible difference side by side. Inktense Ochre is more muted than Grim Rust. They are different kinds of paint: Army Painter Grim Rust is a fluorescent or effect paint and Scale75 Inktense Ochre is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Inktense Ochre is more muted than Grim Rust. They are different kinds of paint.
The same difference applies the other way round: Grim Rust is 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 Grim Rust on the colour wheel See Inktense Ochre on the colour wheel
All matches: Grim Rust equivalents · Inktense Ochre equivalents