Tried to stretch opposite corners to reach 19" and still couldn't get close to 17". The best I can say is closer to 14-15" max. I really wanted one bigger but the price was low enough it was not worth returning and spending the return ship cost.
I was looking for some pillows that are firm enough to last over time but soft enough to lay on. I like taking naps on the couch so wanted something soft to put my face on. The color is as on the website. The material itself isn't quite as fluffy/furry or soft as I was expecting but it is still comfortable. Time will tell how well they will keep their shape.