5-Chloro-2H-benzo[d][1,2,3]triazole is primarily used as a corrosion inhibitor in various industrial applications. It is particularly effective in protecting metals, such as copper and its alloys, from corrosion in environments like cooling water systems and heat exchangers. The compound forms a protective layer on the metal surface, preventing oxidative damage and extending the lifespan of the equipment.

In addition to its corrosion inhibition properties, it serves as a stabilizer in photographic chemicals, helping to maintain the quality and longevity of photographic solutions. It is also utilized in the synthesis of organic compounds, where it acts as an intermediate in the production of pharmaceuticals, agrochemicals, and dyes. Its unique structure allows it to participate in various chemical reactions, making it a versatile component in organic synthesis.

Furthermore, 5-Chloro-2H-benzo[d][1,2,3]triazole is employed in the electronics industry as a surface treatment agent for printed circuit boards (PCBs). It helps to prevent oxidation and ensures reliable performance of electronic components. Its application in these diverse fields highlights its importance in both industrial and chemical manufacturing processes.