Picnic tables range from 6 to 8 feet in length and 27 to 30 inches in width. Tablecloths for picnic tables are at least 84 inches long for 6-foot-long tables and at least 104 inches long for 8-foot-long tables, and 54 inches wide. This won’t give you exactly the standard overhang of 8 inches on all sides, but a shorter overhang on a picnic table can be a good thing—there is less fabric to blow around.