Fiber-shaped stretchable strain and temperature sensors are highly desirable for wearable electronics due to their excellent flexibility, comfort, air permeability, and easy to be weaved into fabric. However, developing fiber-shaped strain sensors with the merits of low detection limit, wide sensing range and good linearity, as well as fiber-shaped strain-insensitive temperature sensors with a monotonic temperature response, high accuracy and good reliability, are still the great challenges. Herein, we prepare an ionogel fiber composed of thermoplastic polyurethane and ionic liquid (IL) by the facile and scalable wet-spinning technique. This ionogel fiber serves as the wearable strain sensor with the ultralow-detection limit (0.05%), ultrawide sensing range (up to 700%), good linearity and high reproducibility, which is capable of monitoring both subtle physiological activities and large human motions. More interestingly, because of the fast response and high resolution to strain, the fiber-shaped sensor can be sewed into the fabric to secretly encrypt and wirelessly translate message based on the principle of Morse Code. In addition, a wearable strain-insensitive temperature sensor is also obtained from ionogel fiber by geometry design. It is found that the “S” shaped temperature sensor can effectively eliminate strain interference on temperature response signals. The inaccuracy of temperature monitoring is within 0.15 °C when the sensor is subjected to 30% tensile strain simultaneously. Moreover, this strain-insensitive temperature sensor shows a monotonic temperature response over a wide temperature range (-15 °C to 100 °C), ultrahigh detecting accuracy of 0.1 °C, and good reliability, owing to the excellent thermal response of IL. This temperature sensor can realize the detection of thermal radiation, proximity and respiration, exhibiting enormous potentials in smart skin, personal healthcare, and wearable electronics
