By Charles 
Bar stools generally should not be used at a standard-height dining table because the seat is too high for comfortable legroom and eating posture. A standard dining table needs standard dining chairs, not bar-height seating.
Most standard dining tables are about 28 to 30 inches high. A regular dining chair seat is usually around 17 to 19 inches high, leaving enough space for thighs under the table and placing the diner at a natural eating height. Bar stools are much taller, often around 28 to 32 inches at the seat, so they would place the user too close to or above the tabletop.
Counter stools are also usually too tall for a standard dining table. Even if someone can sit on the stool, their knees may not fit under the table, and the eating angle can feel awkward. The setup may also be less safe because the user has to climb onto a taller seat beside a low table.
There are a few exceptions. Adjustable-height stools may work if they can lower to standard dining-chair height and remain stable. Some casual spaces use unusual table heights, so measuring is always better than guessing from the name.
For POVISON, use dining chairs with standard-height tables and reserve bar stools and counter stools for kitchen islands, counters, and bar-height surfaces.
