The eating and working surface of a bar-height table is approximately 40 to 42 inches from the floor. Bar-height chair and stool seats measure 29 to 30 inches from the floor, which falls in line with the 10-to-12-inch rule of thumb. If the bar chair has armrests, make sure they're low enough to fit under the table rather than bump into it.
Though not as commonly used as standard bar-height tables, extra-tall bar-height tables are about 48 inches from the floor. Therefore, the seat height that works for them is about 36 to 38 inches from the floor. Extra-tall tables and chairs may be difficult to find. Look for them at specialty bar stool shops and restaurant supply companies, or try an online search.
Counter height is typically 36 inches from the floor. If you have a counter-height bar or counter-height table, sometimes called a "gathering table," you'll need counter-height chairs, which have seats that are about 26 inches from the floor. At furniture stores and especially in garage sales or online used furniture sales, counter chairs and stools are sometimes mistakenly marked as bar stools. Measure the seat height to be certain you're purchasing the height you need.
Standard dining tables measure about 30 inches from the floor; the correct chair seat height for a dining table is around 19 to 20 inches from the floor. Because the seat heights of dining chairs, counter chairs and bar chairs rise incrementally, it can be difficult to tell what you are buying if you go solely by sight. Be safe rather than sorry and bring a tape measure with you on your shopping trip.