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This paper describes a strategy to impart brittle conductive patterns composed of silver nanoparticles with high stretchability and structure‐dependent electrical characteristics. Silver nanoinks are printed on an elastomeric polyurethane acrylate substrate in the form of planar serpentine structures that can effectively mitigate strain concentration. The relative changes in resistance (∆R/R₀) and stretchability are found to strongly depend on the serpentine radius (r) that determines the strain relieving efficiency. Features with small radius of curvature show colossal ∆R/R₀and hold great promise as ultrasensitive stretchable strain gauges. A record high gauge factor of 10⁷is achieved at 12% strain withr= 200 µm. Devices with larger radius of curvature exhibit higher stretchability and much more stable conductance, thus can be used as stretchable conductors. The results demonstrate the versatile functionalities that can be acquired from conventional materials by judicious structural designs.

A unique direct printing method is developed to additively pattern silver nanowires (AgNWs) with length of up to ≈40 µm. Uniform and well‐defined AgNW features are printed on various substrates by optimizing a series of parameters including ink composition, printing speed, nozzle size, substrate temperature, and hydrophobicity of the substrate surface. The capability of directly printing such long AgNWs is essential for stretchable electronics applications where mechanical compliance is required as manifested by a systematic study comparing the electrical and electromechanical performance of printed AgNW features with different nanowire lengths. Such printed AgNWs are used to demonstrate biaxially stretchable conductors, ultrasensitive capacitive pressure sensor arrays, and stretchable electroluminescent displays, indicating their great potential for applications in low‐cost wearable electronics. This strategy is adaptable to other material platforms like semiconducting nanowires, which may offer a cost‐effective entry to various nanowire‐based mechanically compliant sensory and optoelectronic systems.