Introduction: Measurements in endoscopic sinus surgery (ESS) are usually obtained with variable accuracy. We aimed to validate endoscopic multipoint integrated laser systems (EIMLS) for use in ESS, which can acquire measurements within one-hundredth of a millimetre. Methods: 4.4mm flexible endoscopic EIMLS projecting 49 laser points into the view was used to assess simulated anterior skullbase defects. Antero-posterior and lateral measurements were obtained and repeated twenty times by two surgeons. These were compared to measurements with surgical calipers. Intra and inter-observer reliability was assessed. Results: 80 measurements were obtained of simulated skullbase defects by each otolaryngology surgeon and compared to manual measurements. The mean difference shown was 0.56cm. Bland-Altman plot shows low bias (0.044) but wide 95% limits of agreement (-1.8 – 1.9). Conclusion: EIMLS allows reliable and easy to obtain measurements within a simulated ESS environment. Translation of this technology offers promise in a future clinical setting but will require further refinement to improve accuracy.