Binned Duration Flow Tracking (BDFT) method tracks the duration of packet flows in a resource limited environment by storing packets identifying the beginning and the end of a flow in bins, with each bin covering an independent and arbitrary length of time. Bins are “aged” periodically, based on the range of time which the bin covers. A query as to the flow duration returns the bin number which that flow is in; the bin number is then translated into a range of time. Each bin is a counting bloom filter. The size of the bloom filters, range of the count, and number of hashes used are all parameters of the algorithm which affect memory usage, processing required, and accuracy.