Frame size is determined by the size of your image. Generally, you take the image size and add approximately 6-8 inches. That gives you the inside measurement of the frame. You then add the thickness of the frame bar. (Don’t forget to double this measurement, you have two sides on the frame) This gives you the minimum size frame for your job.
Next, look on our size chart and pick the best match. This is the most economical way to size a frame. If you require an exact custom size we can, of course, manufacture any size for you. Example: Image is 12″ x 16″ add 6″ to each measurement, you get 18″ x 22″.
Add 3″ for two frame bars, you get 21″ x 25″. Result: You can use a stock 21×27 or a 23×31 if you want a little more room.