Formamidine hydrochloride is widely used in the synthesis of pharmaceuticals, particularly in the production of antihistamines and antiviral drugs. It serves as a key intermediate in the preparation of various organic compounds, including imidazoles and other nitrogen-containing heterocycles. In agriculture, it is utilized as a precursor for the synthesis of pesticides and herbicides, helping to protect crops from pests and weeds. Additionally, it finds application in the textile industry as a dye-fixing agent, enhancing the colorfastness of fabrics. Its role in chemical research is also significant, where it is employed in the development of new materials and chemical processes.