Used primarily as a dye intermediate in the production of naphthol-based azo dyes, which are widely applied in textile, leather, paper, and printing ink industries for coloring.

It serves as a pH indicator in analytical chemistry, changing from yellow to red in acidic conditions, and is used to detect changes in acidity-basicity in solutions. Additionally, it acts as a reagent for detecting certain metal ions due to its ability to form colored complexes.

Further applications include the synthesis of photographic sensitizers and as a nitration indicator in specialized organic reactions.

There are studies in biochemistry exploring its use as an inhibitor of certain enzymes involved in cellular energy transfer, but due to its high toxicity and explosive properties when dry, handling requires extreme caution, limiting its use to laboratory and research settings.