390 mm equals 39 cm. To know how many centimeters 390 mm corresponds to, we need to know the conversion relationship between millimeters and centimeters. The relationship between millimeters (mm) and centimeters (cm) can be expressed by the following mathematical formula. 1cm is equal to 10 mm, which means that each centimeter is equal to 10mm. To find out how many centimeters 390 mm is, we can divide 390 by 65438. Centimeter is the unit of length measurement, which is equal to 1% of one meter, that is, 65438+ 1/000 of one meter. In the international system of units, the symbol of centimeter is cm, which is widely used, such as measuring the length in daily life, marking the size of articles, engineering construction, medical examination and so on.