The continuous growth of IoT devices that use the 2.4 GHz radio spectrum has motivated research about spectrum occupancy, mainly the dynamic assignment optimization problem of the ISM band. For example, IEEE 802.11-based networks are easily interfered with, due to coexistence with other 2.4 GHz wireless networks, such as IEEE, 802.15.1 and IEEE 802.15.4-basednetworks. This problem causes a degraded performance of these wireless networks, especially inhighdensity areas where several APs (Access Points) are located in the same area to increase throughput. This paper presents MFDCA (Multi-Factor Dynamic Channel Assignment), which is a dynamic channel assignment modular approach for Wi-Fi networks. MFDCA channel assignment is a hybrid modular scheme that can be applied to centralized and distributed design networks. This approach can be used to assign all IEEE 802.11b/g/n standard channels (overlapping and nonoverlapping), and also includes an interference analysis module which uses a number of factors that may affect the transmission quality, such as signal receiver strength indicator (RSSI), signalto interference plus noise ratio (SINR), link quality (LQ), and overlapping factor (OF). MFDCAwas evaluated in a real testbed and results showed that it reduced the packet loss rates (lessthan 5.3%) and improved the quality and reliability of network traffic throughout (29-32 Mbits/s), requiring relatively low sensing process complexity and considering in assignment overlapping and non-overlapping channels from IEEE 802.11 standard.