After a Component has been added to the model, the Mesh ribbon toolbar (Windows) or the 
Mesh contextual toolbar (macOS and Linux) is made accessible. Click the 
Mesh ribbon tab to open the 
Mesh ribbon toolbar (Windows). Click a meshing sequence node in the 
Model Builder and the 
Mesh toolbar displays on the COMSOL Desktop (macOS and Linux).
 
    To measure the volume, area, or length of a selected domain, face, or edge, respectively, click the Measure button (

). The result displays in 
The Messages Window. Using this button, it is also possible to view the coordinates of a selected vertex, the distance between two selected vertices, or the number of entities and the geometry representation (only if you have license for the CAD Import Module) of a geometry object.
 
    The Mesh Toolbar in 1D and 2D contains a subset of the tools in the 3D toolbar. See also 
Measuring Geometry Objects and Entities.