Abstract: Disclosed are various embodiments for searching for items in a catalog using normalized item attributes. A range of values on a normalized scale is determined for an option for an attribute associated with a representative item. The range of values of the representative item is correlated with a first unit on a first scale of item classification. Multiple items are identified based at least in part on the option for the attribute. Each of the items is associated with a respective option for the attribute that has a respective range of values on the normalized scale that overlaps the range of values of the representative item. The respective range of values of one or more of the items is correlated with a second unit on a second scale of item classification.

Abstract: Disclosed are various embodiments for generating classifications for items from normalized item attributes. Multiple attribute options are maintained for an item. Each of the attribute options is associated with a respective range of values on a normalized scale for an attribute. Multiple item classifications are generated for one of the attribute options by mapping the respective range of values for the one of the attribute options to one or more item classifications on each of multiple scales of classification for the attribute.