There are 8 USDA Grades of Beef:

1.  USDA Prime
2.  USDA Choice
3.  USDA Select
4.  USDA Standard
5.  USDA Commercial
6.  USDA Utility
7.  USDA Cutter
8.  USDA Canner

Within a maturity group, marbling (the amount and distribution of intramuscular fat) within the ribeye is the primary determinant of USDA Quality Grade.  Visual evaluation of marbling in the ribeye (at the 12th rib cross-section) are related to differences in eating quality of beef.  Beef cuts with high levels of marbling are more likely to be tender, juicy and flavorful than the cuts with very low levels of marbling.  Studies suggest that beef from carcasses grading at least USDA Select are likely to acceptable in eating quality for most consumers.

        • Beef is graded for quality by U.S. Department of Agriculture (USDA) graders according to standards established by the USDA.
        • Grades are based on the amount of marbling (flecks in fat within the lean) and the age of the animal.
        • These quality grades are an indication of palatability characteristics such as tenderness, juiciness, and flavor.

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Three Top Grades Illustrated

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While there are eight quality grades for beef, the top three Grades available to most consumers are:

PRIME (moderately abundant)

This is the grade of beef that contains the greatest degree of marbling (small flecks of fat that are interspersed with the lean muscle, which contributes to tenderness, juiciness and flavor). It is generally sold to finer restaurants and to some selected meat stores. It is usually higher priced because it is produced in very limited quantities.

CHOICE [moderate]

This is the grade preferred by many consumers because it contains sufficient marbling for taste and tenderness. It is usually less costly than U.S. Prime. Choice falls between Prime and Select.

SELECT [slight]

This is generally a lower-priced grade of beef with less marbling than U.S. Choice. Select cuts of beef may vary in tenderness and juiciness.
Select has the least amount of marbling, making it leaner than, but often not as tender, juicy and flavorful as, the other two top grades.