Quantitative echocardiographic evaluation is important for systemic right ventricles, but its asymmetric shape makes this challenging and time consuming when performed manually. Semi-automated software could make these quantitative measures easier to accomplish in the clinical setting. We hypothesized that semi-automated software would approximate manual measures of right ventricular size and function. Children with hypoplastic left heart who had echocardiograms were prospectively identified. These measurements were performed using manual and semi-automated techniques: end-diastolic and end-systolic area, fractional area change (FAC), dimensions (longitudinal, basal and mid-cavitary diameters), and tricuspid annular plane systolic excursion (TAPSE). Agreement between measures was evaluated. Sixty-three echocardiograms were analyzed. Intra- and inter-observer reliability was acceptable and similar between methods except that inter-observer reliability for the manual method was superior for TAPSE. Correlation between methods was high (r > 0.9, p < 0.001) for most of the measures. Correlation for FAC was r = 0.79, and for TAPSE the correlation was r = 0.61 (both p < 0.001). The percent relative difference between manual and semi-automated methods was less than 6% for most measures. End-systolic area and FAC had a relative difference of 10% and 11% respectively. The only measure with substantial bias between the manual and semi-automated methods was TAPSE which had a relative difference of 52%. EchoInsight® semi-automated software provides similar measures of right ventricular dimensions and FAC in patients with hypoplastic left heart compared to manual measures. Measures of TAPSE do not correlate well between manual and semi-automated methods. Further research is warranted on the use of semi-automated analyses in this patient population.