The increasing global temperature has increased awareness of enhancing Outdoor Thermal Comfort (OTC). OTC has become a primary indicator for the effectiveness of urban environments, which directly affects inhabitants' health, comfort, and quality of life. Consequently, many thermal comfort indices were developed to quantify outdoor thermal comfort; among them was the Universal Thermal Climate Index (UTCI), which is one of the broadly used thermal indexes in evaluating OTC. As another axis of this awareness, several computer-aided design (CAD) software have worked on developing their techniques to increase the accuracy of their outdoor simulations and climate measurements. The paper concerns exploring the potential of the Ladybug as a tool for measuring UTCI through an algorithmic script designed with the Ladybug (ver. 1.6.0) in the Grasshopper interface within Rhinoceros 3D software. The script was applied to two urban neighbourhoods in different climate zones of Egypt, Cairo (an inland city and the capital of Egypt) and New Damietta (a coastal city on the Mediterranean Sea), to investigate its capabilities in simulating and measuring the UTCI of different climate zones in the extreme hot week of the year as an examination period. Results showed that the maximum UTCI value in the coastal neighbourhood decreased from 32.93°C to 31.64°C, while its minimum value decreased from 28.79°C to 27.28 °C compared to the inland neighbourhood. The maximum and minimum UTCI values, hourly data, and the percentages of UTCI heat stress categories for six test locations in each neighborhood were also calculated and compared.