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Mechanical metamaterials at the microscale exhibit exotic static properties owing to their en- gineered building blocks, but their dynamic properties have remained significantly less explored. Their design principles can target frequency-dependent properties and resilience upon high-strain-rate deformation, making them versatile materials for applications in lightweight impact resistance, acoustic waveguiding, or vibration damping. However, accessing dynamic properties at small scales has remained a challenge due to low-throughput and destructive characterization, or lack of existing testing protocols. Here we demonstrate a high-throughput non-contact framework that employs MHz-wave propagation signatures within a metamaterial to nondestructively extract dynamic linear properties, omnidirectional elastic information, damping properties, and defect quantification. Using rod-like tessellations of microscopic metamaterials, we report up to 94% direction- and rate-dependent dynamic stiffening at strain rates approaching 10^2 s^{−1}, in addition to damping properties 3 times higher than their constituent materials. We also show that frequency shifts in the vibrational response allow for characterization of invisible defects within the metamaterials, and that selective probing allows for construction of experimental elastic surfaces, previously only possible computationally. Our work provides a route for accelerated data-driven discovery of materials and microdevices for dynamic applications such as protective structures, medical ultrasound, or vibration isolation.