The Mexameter® is a device that measures simultaneously two major components of skin pigmentation: melanin and hemoglobin.

The measurements are performed by the application of a probe to the skin surface. The probe has a 5 mm aperture that emits radiations. These radiations are reflected by the skin and captured back by the same probe.

The results are expressed as index value for each parameter (melanic index and erythematic index) in arbitrary units on a scale from 0 to 999.