The Intel Core i5-14600K is the objective winner of this comparison, securing a lead in eight of the sixteen evaluated specifications. Its most significant technical advantage over the Intel Core i5-12400 is its L2 cache, which is 167% larger. This substantial increase in cache capacity provides the primary performance edge for the newer processor, distinguishing it as the superior option across the majority of the measured hardware metrics.

Users prioritizing raw processing capabilities should select the Intel Core i5-14600K to leverage its superior L2 cache. Conversely, the Intel Core i5-12400 is the better choice for those focused on power efficiency, as it maintains a 48% advantage in TDP. Choosing between these two components depends on whether your specific requirements favor the increased cache capacity of the newer model or the lower power consumption profile of the older unit.