Analyze a design > Measure > To measure distances
  
To measure distances
You can copy the distance value from the status area (right-click and select Copy Value) and paste it into any Windows application.
Click Apply to use the distance value as input in open commands. Click Close to finish the operation.
When you measure infinite geometry, the value at the worksphere boundary is given as the measurement.
To measure distances,
1. Click Analysis and then, in the Measure group, click the arrow next to Distance.
2. Click Distance. The Measure Output and Distance dialog boxes open.
3. Select a measuring option:
Click Between Pts. Select the From point. Select the To point.
Options...
You can manipulate the distance:
By clicking Horizontal to use the horizontal distance between the projections of the two points onto the active workplane.
By clicking Vertical to use the vertical distance between the projections of the two points onto the active workplane.
By clicking Workplane to use the distance between the projections of the two points onto the active workplane.
By clicking Direction and using the options in the Direction 3D tool to define a 3D direction. Creo Elements/Direct Modeling will project the two points on the direction (line) and use the resulting distance.
Click Distance Between 2 Elements. Select the from element. This can be a vertex, an edge, or a face. Select the to element. This can be a vertex, an edge, a point, or a face. The shortest distance between the elements is displayed graphically with a straight line and a value.
Click Edge Length. Click an edge on the object.
Click Contour Length. Click a contoured edge.
Click Pnt & Edge. Click a point on the object. Click the target edge.
Click Pnt & Face. Click a point on the object. Click the target face.
Click Pnt & Crv. Click a point. Click a curve.
Click Pnt & Surf. Click a point. Click a surface.
* 
Two surfaces are considered to be parallel if the angle between their plane normals or their cylindrical axes is less than 1e-6 degrees.
Click Face & Face. Click a face on the first part. Click a face on the second part.
Click Surf & Surf. To measure the average distance between two parallel surfaces. Click the first surface. Click the second surface.
Click Edge & Face. Click an edge. Click a face.
Click Edge & Surf. Click an edge. Click a surface.
Click Edge & Edge. Click the first edge. Click the second edge.
Click Maximal Distance. Select the edges or faces between which you want to measure the maximal distance. Select a measure direction. Click Calculate. Creo Elements/Direct Modeling displays graphical feedback for the location of the maximal distance. (You cannot measure the maximal distance between a 3D point and an edge or face.)
4. Creo Elements/Direct Modeling displays the distance in the Distance Output.
5. Click the green arrow to send the measurement to a command.
6. Click the green arrow and calculator to send the measurement to the calculator.