A water bath is a piece of scientific equipment used to maintain a stable temperature for extended periods when incubating samples. It is preferred over an open flame when heating flammable substances, and is commonly used to facilitate certain chemical reactions at elevated temperatures.

This equipment is widely used in medical laboratories, universities, research institutions, and in industries such as chemical processing, printing, dyeing, pharmaceuticals, petroleum, and electronics manufacturing. Typical applications include evaporation, distillation, concentration, and constant-temperature heating.