To determine which stool is right for you, measure the height of your counter or table from the floor to the underside of your counter. Make sure to leave between 9″-13″ between the seat and the counter to allow seating.
Kitchen and vanity chairs and stools typically have a seat height of 17" to 18". Bar height stools have a seat height of 28" to 30". Counter height stools have a seat height of 24" to 26". And Spectator height stools have a seat height of 33" to 34".
For more information on choosing stool heights, see here.