Grading standards guarantee consistent quality for growers, wholesalers and consumers, helping the trading, adding value to products and reducing postharvest losses. The main purpose of this study was to evaluate a grading diameter system for fresh market tomatoes in a rotative cylinder equipment in different rotation velocities. Sorting efficiency, based on the standard diameter of THE BRAZILIAN PROGRAM FOR THE HORTICULTURE MODERNIZATION (2003) and mechanical damage incidence for "Carmen" tomatoes were evaluated. The divergent cylinders were in accordance with grade mixing in classes 60 and 80 grading. However, for grade 70 no treatment was in accordance with the mixture percentage allowed, which is 10% of fruit from other classes. The combination of a flat and a helical rubber cylinder, both at 150 rpm, had the highest sorting efficiency, showing low weight loss and respiratory activity rates, values similar to the ones found for control treatments.302334345