Biofuel production, and grain and oil processing produces byproducts, and these can be used in swine diets to reduce feed costs. The nutritional value of byproducts varies greatly with the parent source, the type of processing, and the individual processing plant. Some of the byproducts used are high fibre, and generally high fibre reduces performance, but the digestibility of fibre also varies. DDGS is a commonly used byproduct, and it has a typical nutrient profile similar to corn, but it does alter the fat characteristics when used in high percentages. Bakery byproducts have good nutritional value, though they are often priced higher than other byproducts due to competition for their use. Corn gluten feed has also been included at high levels into diets with success, and could be further utilized by different enzymes or pelleting. Wheat shorts have 85% the nutritional value of corn, and can be included up to 40% for grow-finish pigs. Finally, soybean hulls have higher fibre, protein, and energy than other byproducts, but should only be included up to 5%. Choosing a reliable source for byproducts and sticking with one byproduct can help maintain performance while reducing feed costs.