The performance test of the java apple fruit sizing machine indicate that velocity and inclination angle of the sizing belt, feeding belt velocity and the fruit orientation significantly affects the sizing performance at p < 0.05. The optimum conditions for continuous mechanical sizing were dependant on the variety of the fruit. The optimum sizing performance was characterised by an error ratio of 10.8–16.5% and a throughput capacity of 149.7–195.1 kg h−1. Manual sizing of java apple destined for export feature average ratios of 27.9% in error, 13.3% in damage and a capacity of 107.2 kg h−1. The developed java apple sizing machine could be operated at “zero noticeable damage”, and therefore no additional mechanical damage to the sized fruits.