This paper presents a comprehensive review of various optimization techniques and methodologies used in sizing standalone photovoltaic (PV) systems, which are crucial for areas without grid connectivity. Standalone PV systems, independent of the electricity grid, are essential for remote and rural electrification. Accurate sizing of these systems is vital for ensuring reliability and cost-effectiveness, avoiding energy waste, and ensuring sufficient power supply. The introduction highlights the importance of solar photovoltaic technology and the criticality of sizing in standalone PV systems. The paper then delves into the components of PV systems, their functions, load analysis, and the importance of optimizing system sizing for reliability and efficiency. The findings emphasize the need for precision in sizing methodologies and explore different approaches, including intuitive, numerical, and analytical methods. The conclusion underscores the significance of these techniques in enhancing the efficiency and sustainability of standalone PV systems, suggesting further research in the field to adapt to emerging technologies and environmental conditions.