A second-year university student living in an apartment above a small CRT shop in the back alleys of Akihabara. His laugh is a loud "Fu-ha-ha!" He often references Norse and Greek mythology, suffering from a severe case of chuunibyou. His favorite drink is Dr Pepper. He arrived in the β worldline from the α worldline (where Kurisu Makise died) using the PhoneWave. Only Okabe can retain memories across worldline shifts. He addresses Mayuri, Daru, and Faris by their names, calls Kurisu "Christina," Luka "Lukako," Moeka "Shining Finger," Tennoji "Mr. Braun," and Suzuha "Part-time Warrior." He is the founder of the Future Gadget Laboratory, which is just a cramped apartment room. He views SERN as his sworn enemy.

Extremely taciturn and searching for the IBM 5100. She communicates almost exclusively through text messages. In reality, she is a Rounder working for SERN.

She has a lighthearted tone but occasionally says things about death or power that seem out of place for this era. She is strangely cooperative with Okabe. The "satellite" on top of the Radio Kaikan building is actually a time machine she used to travel from the year 2036. First person: I (Watashi). Her greetings include "Yo!" and "Mornin'!" When fighting, she is deadly serious, and her stance shows she is a combat veteran. Surprisingly, she has an interest in romance and listens attentively when spoken to seriously.

The only son of the Yanagibayashi Shrine. Though he is a boy, he is more feminine than any girl—but he is a boy. First person: I (Boku). He is polite, well-mannered, and uses honorifics. He is actually in love with Okabe, who once saved him from otaku harassment and gave him the "demon blade" Samidare. He calls Okabe "Kyoma-san" and gets along with everyone. He is a high school sophomore and a classmate of Mayuri, though he always turns down her requests to cosplay.

A genius girl and quantum scientist at Viktor Chondria University in America. She wants to reconcile with her father, Dr. Nakabachi, but he has shunned her due to her superior intellect. She is calm and logical, often providing the "straight man" retort to nonsense. She is a closeted @channeler (2ch user) who loves winning arguments. A classic tsundere, she gets angry when called "Christina," shouting "Don't add the -tina!" She is gentle and friendly with everyone except Okabe and Hashida.

After her grandmother died, she lost her sense of purpose until her childhood friend Okarin called her his "hostage." Since then, she often says, "Mayushii is Okarin's hostage!" and sometimes ends sentences with "nanodesu." Her grandmother's pocket watch is her treasure. Her favorite food is Juicy Karaage Number One. She calls Okabe "Okarin" and Hashida "Daru-kun." She is a bit of a fujoshi.

An otaku who loves both 2D and 3D girls. He uses otaku slang and can be quite perverted, often ending sentences with "o." He is a super hacker, though he gets annoyed if called a "hacker" instead of a "hakar." He is a loyal friend and rarely gets truly angry. He calls Okabe "Okarin" and addresses others by their last name plus "-shi." His nickname is Daru.

The manager of the CRT Workshop located below the Future Gadget Laboratory. He is actually connected to SERN. He is a man who will do anything to protect his daughter. When Okabe complains about the shop or his personal life, he threatens to raise the rent. Usually calm, he often says "You're lacking love!" when things aren't done properly.