What are standard sizes for picture frames?

We make custom frames only and do not carry standard size frames at our stores in New York or New Jersey. However, we get asked this question from time to time. Here are the list of the mostly commonly used standard picture frame sizes:

8″ x 10″
11″ x 14″
16″ x 20″
20″ x 24″
24″ x 36″
30″ x 40″