Some demonstrative embodiments include apparatuses, devices, systems and methods of determining one or more active channels. For example, an apparatus may include an energy measurement component including circuitry to measure energy on a plurality of wireless communication frequency channels; a mapping component configured to determine a two-dimensional energy detection map of an Access Point (AP) scan, the two-dimensional energy detection map including a plurality of energy values mapped to a plurality of time slots and to the plurality of frequency channels; and an channel detector component configured to detect one or more active channels of the plurality of wireless communication frequency channels, based on the two-dimensional energy detection map.