Abstarct: The design of blast patterns and blast management in open-pit mining is carried out with the aim of achieving an appropriate degree of fragmentation, reducing undesirable phenomena such as ground vibration, air blast, damage to bench faces, and excessive flyrock, while ensuring the operational and economic feasibility of blasting operations. Proper fragmentation can significantly reduce mining costs by facilitating and improving the efficiency of loading, hauling, crushing, and grinding operations. Various methods are available for measuring the degree of fragmentation, which are classified into direct and indirect methods. Direct methods include sieve analysis, while indirect methods include observational, empirical, and digital image processing techniques. The objective of this research, conducted at the Muteh Gold Mine, is to achieve an optimal particle size distribution. To accomplish this, the blast-induced fragmentation at the Muteh Gold Mine was first evaluated using the Split-Desktop image analysis software. After analyzing previous blasts, the blast design (powder factor and charge distribution) was carried out baxsed on empirical formulas and the rock fragmentation index. Following the calculation of the powder factor and considering the relationships between powder factor and other blasting parameters, four blasting patterns were proposed. These four blasting patterns were analyzed in terms of fragmentation using the image analysis software, and finally, F20, F50, F80, and the maximum fragment size were determined. The results indicated that the proposed blasting pattern No. 4, with an F80 of 11.34 cm and a pattern of (2 × 2.8), showed superior performance compared to the other patterns in terms of fragmentation quality and cost efficiency and was therefore selected as the optimal pattern. Furthermore, the application of air decking and the reduction of explosive charge in the back-row blastholes decreased backbreak and improved bench stability and blasting safety.