Background/aim: Giant ventral incisional hernias (GVIHs) are hard to manage for surgeons. This problem was resolved in 1990 with the components separation technique (CST). We aimed to compare endoscopic and conventional CST for GVIHs and find a new anthropometric calculation.Materials and methods: In this prospective nonrandomized clinical trial, 21 patients were treated with endoscopic or conventional CST between 2012 and 2016. Eight patients (38.1%) were operated endoscopically and 13 (61.9%) conventionally on the basis of preoperative tomography results, hernia surface area (HSA), number of recent abdominal operations, comorbidities, and the presence or history of ostomy. Groups in which prosthetic material was applied were also compared with groups in which it was not.Results: There was no statistically significant difference between endoscopic and conventional CST groups in terms of complications. A weakly statistically significant difference (P = 0.069) was found between the components separation index (CSI) of mesh-applied and not-applied patients. HSA/body surface area (BSA) was statistically significantly different between endoscopic and conventional CST groups.Conclusion: According to our results, HSA/BSA and CSI are statistically successful for preoperative prediction of mesh placement. Furthermore, HSA/BSA preoperatively successfully predicts whether conventional or endoscopic CST should be used in patients with GVIH.