You want a changing table that allows you to do your thing without it putting strain on your back. If you’re tall, you can opt for a taller table, some of which can be up to 43 inches (or 3.5 feet) high. If you’re shorter, look for a table in the 35 to 38 inch range.
A good idea is to test a table out in the store and get a feel for its proportions. If it’s too tall, you’ll be pulling your elbows up awkwardly to change your baby, which will get irritating after your fifth diaper of the day. Don’t forget to factor in the height of the changing pad as well.
Ideally, the highest part of the table should hit around hip height.