Feed value describes the actual nutritional value of a raw material or complete ration for an animal. It encompasses not only the content of energy and protein but also the digestibility, amino acid profile, and biological availability of nutrients. A high feed value means that a large portion of the offered nutrients is effectively utilized by the animal.

The interpretation of feed value differs per animal species. In ruminants, rumen fermentation and fermentable cell walls play a central role, while in monogastric animals and aquatic species, digestibility in the gastrointestinal tract is paramount. Feed value is a core concept in rational ration calculation and cost-efficient production.