You can choose from a variety of sizes depending on your budget and the size of pizza oven you want to build. We recommend 14” in diameter, however 12” or 16” may also work well. You need approximately ½ inch thickness for best results. The bigger stones provide a more even cooking surface and will take longer to heat up. The smaller stones are going to be quicker at heating, however they may not give you as good of results in terms of evenly cooked pizza crust.