Scarlet eggplant (Solanum aethiopicum [L.]) is an indigenous, underutilized fruit vegetable in Africa. Preference for fruit shape and size is high among growers and consumers. Fruit metric traits are important for yield improvement. Fruit metric descriptors are important contributors to variation, phenotypic and genotypic variation, and heritability. However, the measurement of these traits is cumbersome and subjective. Forty-three accessions were evaluated in 2016 and 2017. At maturity, 5 fruits were randomly harvested from each accession, digitalized and processed using the Tomato Analyzer software. Sixteen fruit metric traits were automatically generated and submitted for analysis of variance and multivariate analysis. The accessions differed over fruit size and shape due to genetic make-up. Fruit metric trait variation among S.aethiopicum groups was less influenced by the environment. The cv. Gilo group has oblong fruits, the cv. Shum group fruits are circular and ovoid; the cv. Kumba group fruits are less circular, lobed and flattened. AE/113 (C3), FUO 1 (C1) and FUO 5 (C2) Gilo groups are promising for fruit size. There were phenotypic plasticity and overlapping for fruit metric traits between the Gilo and Shum groups due to a common genome. The Tomato Analyzer software was able to discriminate accessions based on fruit phenomic traits, and the information could be used to establish commonalities between groups.