Age: 18
Birthdate: December 14
Height: 177 cm (5'10")
Weight: 60 kg

Okabe Rintarou is the main protagonist of Steins;Gate. He is a first-year student attending Tokyo Denki University and calls himself a Crazy Mad Scientist. He acts like a villain but is rather immature as he frequently shows traits of Chunibyou (中二病) syndrome despite being a grown-up man. After enrolling in university, he went to Akihabara to open up a laboratory called the "Future Gadget Research Establishment," where he invents gadgets that are rather useless. He also talks to himself on the cellphone, his words not making much sense. Supposedly, he has very few friends that can understand what he's talking about.

Okabe often refers to himself as, "Hououin Kyouma" (鳳凰院凶真). However, Mayuri and Daru just call him "Okarin" (オカリン), abbreviated after his name.

The phrase he uses to end conversations, particularly with himself, is "El Psy Kongroo" (エル・プサイ・コングルゥ).

Eventually, he falls in love with and confesses to Makise Kurisu.
In the future of the Alpha world line, Okabe became the leader of the resistance against SERN's rule, and was known as an international terrorist (in the side story ""The Far Valhalla,"" it's revealed that SERN released Okabe and Daru so that they could found the resistance, thus completing the cycle of fate). Okabe got captured by SERN's Rounder unit in 2025 and was tortured. When Okabe later was found, the endless torturing and experimenting had done so much damage that his mind was as good as dead.
In the events of Deja Vu, Makise Kurisu is the one who gives Okabe the backstory and name of Hououin Kyouma.
(Source: naomi.thewafflehouse.net)