This study presents an evaluation of human exposure levels due to WiFi signals. Up to now, human exposure to electromagnetic fields has been measured using methodologies and system configurations that account for the worst-case exposure conditions. However, more accurate empirical data are needed, since most of the time the worst case is too pessimistic to be considered for quantifying the actual existing conditions. In this work, a novel methodology to determine realistic exposure values due to a WiFi Access Point is defined. By means of this methodology, the contribution of this Access Point to the total WiFi exposure in the 2.4 GHz band is assessed, as well as day and night exposure due to a Wireless Local Area Network (WLAN).