Short-term memory and working memory are two distinct concepts that have been measured in simple and complex span tasks respectively. A new span task was designed to manipulate a chunking factor while using a procedure similar to simple span tasks. This span task allowed studying the interaction between storage and processing in working memory, when processing is fully dedicated to optimizing storage. The main hypothesis was that the storage × processing interaction that can be induced by the chunking factor is an excellent indicator of intelligence because both working memory and intelligence depend on optimizing storage. Two experiments used an adaptation of the SIMON® game in which chunking opportunities were estimated using an algorithmic complexity metric. The results show that the metric can be used to predict memory performance and that intelligence is well predicted by the new chunking span task in comparison to other simple and complex span tasks.