if you ask me, not all chairs are created equal. The width of your chairs is a key, and often overlooked, factor in calculating seating capacity. A wider chair will naturally take up more space along the table's circumference.
A 60-inch round table is most commonly referred to as a 5-foot (5') round table. Since there are 12 inches in a foot, a 60-inch diameter is exactly 5 feet across.
Fitting 10 people is possible, but "comfortably" is subjective. is a very tight fit and is not recommended for formal dinners with large place settings. It works best for casual gatherings, parties, or events with slim chairs where guests are not seated for an extended, multi-course meal.
For proper guest flow and server... This provides a comfortable walkway and ensures people can easily move in and out of their seats without disturbing other guests.
The complexity of your place settings plays a major role in determining how many people can fit at the table. A more elaborate setup requires more table-top real estate per person, reducing the capacity.