The size of a pipe organ is always described in terms of stops. A stop is one set of pipes that goes from the bottom of the keyboard to the top of the keyboard. While there is no hard and fast rule regarding size of pipe organs, a good method for determining an appropriate range of size for your church is 5 – 10 stops for every 100 people of seating capacity. If your church seats 100 then you should consider an organ of 5 – 10 stops. If your church seats 500, then you can consider an organ of 25 – 50 stops.