A time-temperature indicator indicates the useful shelf life of an associated product which may be affected by the passage of time and an applied temperature. A creeping material has a first end connected to a first fixed location and a second end connected to a load applying device such as a spring. In response to application of the load applying device, the passage of time, and the application of various temperatures, the creeping material will increase in length in a known manner. An indicator associated with the creeping material indicates whether the passage of time and application of various temperatures have caused the associated product to exceed its useful shelf life.