A benchtop pH meter is an electronic device that is used in a variety of sectors, including waste water, drinking water, food and beverage, chemical, and pharmaceutical testing, to determine the acidity and alkalinity of liquid or semi-solid samples. Typical tabletop pH meters have a measuring electrode, a reference electrode, and a meter. The measuring electrode detects hydrogen ions [H+] and measures pH as the sample surrounds the glass bulb at the end.

A modest voltage output fluctuates with the concentration of H+ ions in the sample, which the meter measures and displays in pH units. Benchtop pH meters come in a range of measuring modes, including pH, mV, ion, and conductivity.

Temperature compensation is essential since the pH electrode is temperature sensitive. The millivolt (mV) output from the pH electrode will vary in response to the temperature of the sample. This is the outcome of a direct change in the sample's H+ ion activity and compound ionization. Temperature correction is possible in both manual and automated modes, depending on the kind of pH meter.