Running a kingdom seems like one of the hardest jobs anyone can take. Unfortunately, poor Kazuya Souma is forced into the job in order to keep himself from being sold off. Summoned to a new world, Kazuya is told that, as a hero, he would be a good trading item for the kingdom…since they are literally broke. Using his quick thinking and natural logic, Kazuya took it upon himself to help the failing economy in this new kingdom and then ends up being dubbed the new king. Our summoned hero Kazuya has already shown that he’s a truly intelligent young man who isn’t like most isekai protagonists blessed with OP powers and abilities.

Tanya Degurechaff wasn’t always a young girl gifted with military intelligence and powerful magical abilities. Originally, Tanya was a high-end businessman who was killed by an angry ex-employee. Reborn in a strange WW2-like world, Tanya now uses her original smart micromanagement skills to coordinate attacks on various enemies and to somehow find a means to kill off the being that made her into this little girl. Tanya is a truly nightmare-inducing soldier but her intelligence is second to none in the world of Saga of Tanya the Evil!

Trapped in a game that was meant for deletion, a gamer has now assumed the role of his in-game avatar named Momonga. Forced to now take charge of his guild of NPCs turned lifelike, Momonga not only needs to run the guild but also find a means to take over this virtual landscape. Powerful, cunning, extremely innovative, and smart, Momonga is an isekai protagonist that proves brain and brawn are a mesmerizing combination.

Mikami Satoru died protecting his friend in his previous life and when he reawakened in a new world he quickly learned he wasn’t human anymore but now a slime. Named Rimuru Tempest in this new “life” the once weak slime slowly began to prove that ingenuity can accomplish almost anything. Absorbing various enemies and abilities, Rimuru became a truly powerful being that continues using intellect to overcome challenge after challenge. Next time you think a slime might be a dumb monster remember that it could be the next Rimuru capable of beating you in a literal second!

Our last entry on the Top 5 Smartest Isekai Protagonists goes to the legendary devil in glasses, Shiroe from the world of Log Horizon. Like most isekai heroes, Shiroe was a gamer who was trapped alongside thousands of others in the world of Elder Tale. Shiroe could have succumbed to depression like many others but instead, he began using his clever mind to keep the world from spiraling into destruction. Shiroe would begin creating a guild filled with various members and use his knowledge of the game to prevent lawlessness from taking hold. Shiroe might look scrawny and weak compared to the various other classes in Elder Tale but when he pushes his glasses up, be prepared for his tactician's brain to activate.