For browser cache cleanup, to consider for eviction a data item stored in a cache of a browser application in a device, a probability that the data item will be needed again during a period after the eviction is computed. A type is determined of a network that will be available at the device during the period. A cost is computed of obtaining the data item over a network of the type, from a location of the device during the period. Using the probability and the cost, a weight of the data item is computed. The weight is associated with the data item as a part of associating a set of weights with a set of data items in the cache. The data item is selected for eviction from the cache because the weight is a lowest weight in the set of weights.