A calculating device including; a controller configured to execute, for a multicore processor, a first calculation process of calculating a first performance value of a first code executed by the first core and including a first access instruction by executing a first simulation, a second calculation process of calculating a second performance value of a second code executed by the second core and including a second access instruction by executing a second simulation, a synchronization process of synchronizing the first and the second simulations when the first access instruction is executed in the first simulation, and a correction process of correcting the first performance value, by executing a third simulation to simulate an operation of the cache memory when the first core accesses the main memory through the cache memory in accordance with the first access instruction, after the synchronization by the synchronization process.