One good hours, minutes and seconds calculator is the one found at DollarTimes.com. Another example is the hours, minutes and seconds calculator found at TimeandDate.com.
The calculator on DollarTimes.com can be used to calculate the amount of time that somebody spends doing a specific task. This calculator displays results in the same hours, minutes and seconds format, and it also converts results to the amount of time in seconds, minutes and hours, respectively.
The hours, minutes and seconds calculator on TimeandDate.com calculates the duration of time between two moments in time. The calculator also has a built-in feature that allows users to use time-zone conversion for increased accuracy.