Disodium hydrogen phosphate (Na₂HPO₄) is a sodium salt of phosphoric acid. It is a white powder that is highly hygroscopic and water soluble. It is therefore used commercially as an anti-caking additive in powdered products.

It is also known as disodium hydrogen orthophosphate, sodium hydrogen phosphate or sodium phosphate dibasic. It is commercially available in both the hydrated and anhydrous forms pH of disodium hydrogen phosphate water solution is between 8.0 and 11.0

Disodium phosphate is used in dyestuffs and metal treatment. It is also used in conjunction with trisodium phosphate in many steam-boiler applications. It supplies the inventory of free phosphates to retard calcium scale formation.

DSP is also used in Metal cleaning, as a Buffer in Textile Processing, In dyestuffs for faster dispersion, Important ingredient in fire proofing formulations, For purification of clays, For manufacture of opal glass.

It is available in both Crystals & Anhydrous form.