To determine the size of your cloth you need to know:

Once you have these dimensions, to determine the tablecloth size,
add the drop X 2 to each dimension of your table. 

Example:      Table size is 30"x72"; desired drop is 12"

                    12" (drop size) X 2=24" 

                    Add 30" + 24"= 54"

                    Add 72" + 24"= 96"

                    CLOTH SIZE= 54" X 96"

A few things to remember, if a square or rectangular (also called oblong) tablecloth has a drop to the floor, you will need to order with rounded corners, otherwise, the corners will drag on the floor.

When ordering an oval shaped tablecloth, our standard oval is shaped like a 
racetrack.  If your oval is more "egg-shaped" and you need 
the drop to be exact, you would need to send a template 
of the tabletop for us to use as a pattern.

Round tables are measured by their diameter.  
Some standard sizes include 60" rounds, 72" rounds.

120" round tablecloths go to the floor on 60" round tables.
132" round tablecloths go to the floor on 72" round tables.