Physics learning in the digital era faces the challenges of cognitive overload and a decline in students' attention spans toward abstract and dense material. Innovative strategies are required to bridge the efficiency of material delivery with the depth of problem analysis. This study aims to examine the effectiveness of the Microlearning-Based Case Study strategy in improving students' conceptual understanding and critical thinking skills in physics. The research employed a quasi-experimental method with a non-equivalent control group design. The research sample consisted of 64 eleventh-grade students at SMA Negeri 51 Jakarta, selected through a purposive sampling technique. The research instruments included two-tier multiple-choice tests to measure conceptual understanding and essay tests for critical thinking skills, both of which were expert-validated. Data were analyzed using Normalized Gain (N-gain) and t-tests via jamovi software version 2.3. The results indicated that the developed learning media was categorized as highly feasible (96.25%). The implementation of this strategy significantly improved learning outcomes, with the experimental class achieving an N-gain score of 0.74 (High) for conceptual understanding and 0.71 (High) for critical thinking, significantly outperforming the control group (p < .001) with a very large effect size (d > 1.5). In conclusion and implications, the Microlearning-Based Case Study strategy is effective in mitigating cognitive load while sharpening scientific reasoning through real-case analysis. The researchers suggest that educators integrate digital micro-content with contextual scenarios to create more adaptive and meaningful physics learning.