Content delivery is adapted based on network congestion. A method identifies multiple types of content, including a first type and a second type. The method receives, via a network, a first upload request to upload content of the second type from a client device and a second upload request to upload content of the first type from the client device. The method also determines a degree of congestion of the network. This includes obtaining historical latency data for the network and estimating a latency of the network based at least in part on the historical latency data. The method also determines whether the degree of congestion satisfies a congestion criterion. When the degree of congestion of the network satisfies the congestion criterion, the method prioritizes the first type of content over the second type of content and delays the first upload request while granting the second upload request.