To investigate the relationship of contrast sensitivity (CS) with binocularity, eye dominance, and interpupillary distance at various spatial frequencies in healthy adults. Method: Thirty-seven healthy adults (age range, 19-45 years; 27 males) were included. Binocular and monocular measurements of CS were performed with Automatize ClearChart 2 test on monocular (right and left) and both eyes at low-(1.5 cpd), mid-(6 cpd), and high-(18 cpd) spatial frequencies. Eye dominance was determined with

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... he Hole-in-card test and interpupillary distance was measured with PlusOptics photo scanner, and the results were compared statistically. Results: Eye dominance was identified in 35 (94.59 %) subjects with the right eye being dominant in 23 (65.7%) subjects. The logarithmic CS (logCS) in the dominant eye, non-dominant eye, both eyes were 2.58±0.29, 2.62±0.37, and 2.50±0.00, respectively at 1.5 cpd; 2.54±0.16, 2.50±0.00, and 2.50±0.00, respectively at 6 cpd; and 5.46±2.49, 5.26±2.61, and 3.82±1.82, respectively at 18 cpd. The logCS did not significantly differ between dominant and non-dominant eyes. Binocular logCS was lower than monocular logCS significantly at 18 cpd (p=0.001). The interpupillary distance (mean, 58.78±3.63 mm) was not correlated with binocular logCS. Conclusions: Dominant eye was similar to non-dominant eye in terms of CS function at all frequencies in healthy adults. No functional relationship was detected between interpupillary distance and binocular CS. Binocular CS function showed individual differences at high-spatial frequency in healthy adults.