Basic Green 4 is widely used as a dye in various industries, particularly in the textile sector for coloring silk, wool, and cotton fabrics. It is also employed in the paper industry to produce colored papers and in the leather industry for dyeing leather products. In biological research, it serves as a stain for microscopy, helping to visualize cellular structures and microorganisms. Additionally, it is utilized in the aquaculture industry as an antifungal agent to treat fish eggs and prevent fungal infections. Its vibrant green color makes it a popular choice in the manufacture of inks and coatings as well.