Diabetes is a chronic disease requiring frequent monitoring. However, traditional methods are invasive and can cause discomfort. Although prior studies have focused on various microwave and metamaterial geometries in noninvasive sensor applications, they exhibit multiple limitations, including the need for large sample volumes and complex fabrication processes. In this study, a noninvasive microwave sensor was designed, fabricated, and evaluated for fingertip glucose detection. The proposed sensor comprises a single-metal-layer coplanar waveguide with four nested split-ring resonators on an FR4 substrate to enhance electric field confinement and maximize the interaction with biological samples. Experimental validation was performed using a Vector Network Analyzer with various concentrations of glucose samples ranging from 100 to 400 mg/dL. The sensor exhibited a general structural resonance near 4.18 GHz, whereas distilled water measurements exhibited a resonance at 3.584 GHz, which shifted with increasing glucose concentration, yielding a sensitivity of approximately 36.4 kHz/(mg /dL). These findings highlight the potential of the compact microwave metamaterial sensor as a foundation for real-time glucose-monitoring systems.