This disclosure relates to determining load and estimating throughput of wireless networks by a wireless device. According to some embodiments, the numbers of active downlink and uplink nodes in a wireless network may be determined. Channel utilization of the wireless network may also be determined. An uplink data rate and a downlink data rate of the wireless device in the wireless network may be estimated. Based on the numbers of active downlink and uplink nodes, channel utilization, and the uplink data rate and a downlink data rate of the wireless device, the maximum possible uplink throughput and downlink throughput of the wireless device in the wireless network may be estimated. Such throughput estimates may be used to select a wireless network to join from among multiple available wireless networks.