Methods, systems, computer-readable media, and apparatuses for crowdsourcing the synchronization status of a network are presented. In various embodiments, a server receives a synchronization status of a base station associated with the network. If the synchronization status indicates that the network is synchronous, the server collects information for computing time correction data. The server may send the time correction data to the mobile device for use in determining the position of the mobile device when the mobile device is connected to the synchronous network.