This study investigates the potential of using crumb rubber as a partial sand replacement in concrete, addressing environmental concerns related to rubber waste disposal and the depletion of natural aggregates. The research aims to identify optimal ratios of crumb rubber, silica fume, and cenospheres while assessing the impact of crumb rubber on concrete’s compressive strength. By integrating crumb rubber (up to 10% sand replacement), silica fume, and cenospheres into concrete mixtures, the study evaluates both workability and compressive strength. The results reveal that while crumb rubber significantly reduces compressive strength, the inclusion of silica fume and cenospheres mitigates this effect. The ideal mix consists of 10% crumb rubber, 20% silica fume, and 10% cenospheres. However, the observed low workability suggests that further adjustments, such as increasing the superplasticizer dosage, may be necessary. Overall, this research demonstrates that crumb rubber can be effectively utilized in concrete as a sustainable alternative to natural aggregates, providing an environmentally friendly solution for rubber waste management.