Upcycling is the process of converting waste materials or useless products into new materials or products of better quality or for better environmental value.

Upcycling is the opposite of downcycling, which is the other half of the recycling process. Downcycling involves converting materials and products into new materials of lesser quality. Most recycling involves converting or extracting useful materials from a product and creating a different product or material.[2]

For example, during the recycling process of plastics other than those used to create bottles, many different types of plastics are mixed, resulting in a hybrid. This hybrid is used in the manufacturing of plastic lumber applications. However, unlike the engineered polymer ABS which hold properties of several plastics well, recycled plastics suffer phase-separation that causes structural weakness in the final product.

In developing countries, where new raw materials are often expensive, upcycling is commonly practiced, largely due to impoverished conditions.