It has the appearance of reddish brown crystals with melting point 199 °C and maximum absorption at 520(357) nm.

Similar dyes include Oil Red O, Sudan III, and Sudan Black B. Staining is an important biochemical technique, offering the ability to visually qualify the presence of the fatty compound of interest without isolating it.

For staining purposes, Sudan IV can be made up in propylene glycol.

[citation needed] The idea is to use a moderately apolar solvent to solubilize the dye allowing it to partition into the highly apolar fat without the solvent solubilizing the fat to be stained.

In industry, it is used to color nonpolar substances like oils, fats, waxes, greases, various hydrocarbon products, and acrylic emulsions.