A sensing system comprising: a sensor tag; a calculator; and a center, wherein the sensor tag includes a sensor that measures at least one of a physical quantity and a chemical quantity, a memory that stores an expiration date and a correction coefficient value of the sensor, and individual recognition information, and a transmission unit that transmits a measurement value measured by the sensor and the individual recognition information, and the expiration date and the correction coefficient value of the sensor to the calculator, wherein the centrer includes a storage unit that stores an expiration date and a correction coefficient value which are more accurate than the expiration date and the correction coefficient value stored in the memory of the sensor tag for each piece of individual recognition information, and a transmission unit that transmits the accurate expiration date and coefficient value depending on the individual recognition information to the calculator, wherein the calculator includes a transmission unit that transmits the individual recognition information of the sensor tag to the center, a reception unit that receives the individual recognition information and the measurement value from the transmission unit of the sensor tag, and receives the accurate expiration date and correction coefficient value from the center, a determination unit that determines whether the accurate expiration date from the center has elapsed, and a processing unit that corrects the measurement value using the correction coefficient value from the center, and wherein the calculator corrects the measurement value using the expiration date and the correction coefficient value of the sensor in the processing unit in a case where information exchange with the center cannot be performed. a sensor tag; a calculator; and a center, wherein the sensor tag includes a sensor that measures at least one of a physical quantity and a chemical quantity, a memory that stores an expiration date and a correction coefficient value of the sensor, and individual recognition information, and a transmission unit that transmits a measurement value measured by the sensor and the individual recognition information, and the expiration date and the correction coefficient value of the sensor to the calculator, wherein the centrer includes a storage unit that stores an expiration date and a correction coefficient value which are more accurate than the expiration date and the correction coefficient value stored in the memory of the sensor tag for each piece of individual recognition information, and a transmission unit that transmits the accurate expiration date and coefficient value depending on the individual recognition information to the calculator, wherein the calculator includes a transmission unit that transmits the individual recognition information of the sensor tag to the center, a reception unit that receives the individual recognition information and the measurement value from the transmission unit of the sensor tag, and receives the accurate expiration date and correction coefficient value from the center, a determination unit that determines whether the accurate expiration date from the center has elapsed, and a processing unit that corrects the measurement value using the correction coefficient value from the center, and wherein the calculator corrects the measurement value using the expiration date and the correction coefficient value of the sensor in the processing unit in a case where information exchange with the center cannot be performed.