Items, for example grocery items in a shopping cart or warehoused items being inventoried, are counted by electronically registering flickers from tags attached to, or incorporated into, the items. The registration takes place during an interval of time equal to the flicker repetition rate of the tags. For example, each item's tag might flicker out an identifying signal (preferably from an LED in the tag) in about a thousandth of a second, and repeat this flicker once a second. A detector registers all of the flickers from all of the items during a one-second interval, and thereby counts the items because each will have flickered once during that time. Other items, with different identifying flickers, can be counted during the same interval. Thus, large numbers of various tagged items can be counted rapidly.