The 2% oxalic acid solution is a dilute solution of the dicarboxylic acid oxalic acid (C2H2O4). Oxalic acid occurs naturally in many plants and can also be produced synthetically. In this diluted form, it retains its acid properties but is less concentrated than pure oxalic acid.

In laboratory applications, the 2% oxalic acid solution is often used for decalcification or rust removal. In biology and medicine, it is a common means of preserving urine samples because it inhibits the growth of bacteria while stabilizing urine components.

In the food industry, oxalic acid is used as an acidity regulator, while in the textile industry it is used to bleach textiles. In analytical chemistry, it can serve as a reducing agent.