Abstract: A temperature compensated gauge for measuring and indicating the quantity of a gas within a pressurized system is provided, which, in addition to achieving a degree of accuracy appropriate for most practical applications, is characterized by qualities of simplicity, reliability and ruggedness. The last-mentioned qualities render the improved gauge especially suited for use in possibly adverse environments, such as for monitoring the remaining supply of compressed natural gas or analogous fuels on board a moving vehicle. The improved gauge is predominantly electrical in nature and employs a limited number of commonly available and relatively inexpensive components, which enhances its practicality for wide spread utilization in virtually any application where measurements of the pressure of any confined gas must be compensated for the effects of temperature in order to provide an accurate indication of the quantity of gas in the system under variable ambient temperature conditions.