The paper suggests a model for selection tasks that are widespread in modern interaction on the WWW, as well as the means to evaluate performance as hum an processor throughput. Selection tasks are considered the combination of choice and movement stages, which are traditionally modelled with Hick- Hyman and Fitts’ laws respectively. However, as the former seems to fall short in most real interactions, we propose the model based on visual search time (VST) instead. Search area size (S 0), sought element size (S) and the number of alternatives (N) were elected as primary factors for VST, although vocabulary size and number of search keys are also considered. In the result of experimentation with 28 subjects of different age groups, VST was suggested as the logarithm of the ratio between S 0 and S, with N not being significant. Index of selection difficulty (ID S) is proposed based on Fitts’ ID, as well as subsequent notion of selection throughput (TPS), whose mean value in the experimentation amounted to 12.6 bit/s. The models might assist in creating more usable web interfaces, justifying interface elements’ and blocks’ sizes and hierarchy and allowing the eval uation of various interface designs via selection tasks throughput performance measure.