I just looked the pattern over - I think the 14 1/2" on the outside was just a mistake - it could also be extra so after you quilt the piece you can trim it to size - I don't think that will make much difference. On the inside it says that the inside pieces are smaller than the outside - it has pics showing the two pieces that you need to cut - it does seem to be a little confusing but it looks like it will work. Sometimes when my brain won't engage if you walk away and give it 24 hrs or whatever then when you come back it will all fall in place. good luck - its a very cute bag.