— Rin, speaking to Haruka Nanase
|Also known as|| Rinrin|
Rin-chan (by Nagisa)
Matsuoka-senpai and Rin-senpai (by Aiichiro)
|Age|| 17 (Free!)|
19 (Dive to the Future)
|Height|| 145 cm (4'9") (High☆Speed!)|
177 cm (5'10") (Free!)
179 cm (5'10") (Dive to the Future)
|Weight|| 39 kg (86 lb) (High☆Speed!)|
68 kg (150 lb) (Free!)
|Occupation||Aspiring Professional Athlete|
|Affiliation|| Samezuka Academy |
Australian Middle School (former)
Iwatobi Elementary School (former)
Sano Elementary School (former)
|Function|| Australian Swimming Club and Shikou GSSC in Japan|
Captain - Samezuka Academy Swim Club (retired)
Iwatobi Swimming Club (former)
|Swim Style|| Butterfly (specialty) , Breastroke, Individual Medley
events = 50m free
|Relatives|| Toraichi Matsuoka (father, deceased)|
Miyako Matsuoka (mother) 
Gou Matsuoka (younger sister)
Kyou Matsuoka (grandmother)
|Light Novel||Chapter 1|
|Japanese|| Mamoru Miyano|
Akeno Watanabe (Child)
|English|| Vic Mignogna (2014-2018)|
Austin Tindle (2019-Present)
Maxey Whitehead (Child)
Rin Matsuoka (松岡 凛 Matsuoka Rin) is one of the main characters of the anime series Free! and the light novel High☆Speed！ He is a freestyle and butterfly swimmer on Samezuka Academy's swim team and is made team captain after Seijuro Mikoshiba graduates from Samezuka Academy. He is currently training with a professional coach in Sydney, Australia and has qualified to compete on the global level during the All-Japan Invitational.
Rin is a muscular young man with semi-long, maroon-colored hair, red eyes and shark-like teeth. His fall and winter school uniform consists of white trousers, a black t-shirt, a buttoned up white jacket and black shoes. During the spring and summer, his uniform consists of white trousers, a black polo with a pink collar, and black shoes. When swimming in competition, he wears black, long-legged swimskins with a red pattern. His school bag is a red messenger bag with the word "shark" printed on the outside. He is often seen wearing a baseball cap.
When young, Rin displays great passion and competitiveness for swimming, as well as teamwork. As years passed, his ideals about swimming drastically change and he doesn't care much about the relay trophy he wins during elementary school, becoming obsessed with competing and winning against Haruka Nanase.
As a student at Samezuka Academy, he observes the Iwatobi High School Swim Club practicing and having fun together and is notably morose when he sees how happy they are together while he stands alone. His isolation, however, is self-imposed due to his taking on the goal of meeting his deceased father's dream of becoming an Olympic swimmer. At times, Rin displays a softer side, showing concern for his friends' well-being and acting as a mentor towards Gou Matsuoka (Rin's younger sister) and Aiichiro Nitori (Rin's temmate) . Following graduation and beginning his training with Mikhail Makarovich Nitori in Australia, Rin seems more relaxed and playful, bringing his friends Australian souvenirs and sharing jokes with Sosuke.
Toraichi Matsuoka (Rin's father) is a fisherman by trade who dies during a storm that claims his life and the lives of his crew while only three kilometers from shore when Rin is very young. Rin states that he has few memories of his father and cannot even recall what his father looked like, as he would be gone for days while at sea. Rin wants to become an Olympic swimmer because he believes that by following this path, he will be able to remember his father's face. He also puts his swimming goggles on in the same way his father used to do, by pulling the strap back and letting it snap onto the back of his swim cap.Rin joins the Iwatobi Swimming Club in elementary school because it was his father's old swim club and where his father and his teammates won a relay. Rin wants to create a winning relay in order to emulate his father as he starts down the path to becoming an Olympic swimmer.
In elementary school, Rin is in the same community swimming team with Haruka Nanase, Makoto Tachibana and Nagisa Hazuki and he is instrumental in motivating the group to swim a relay. After winning the tournament, he leaves Japan to attend a school in Australia known for their strong swimming program.
Rin enjoys swimming, but finds attending school and living in Australia to be a big adjustment. His homestay parents, Russell and Lori, are kind people who care for him and help him, even buying him a dog they name "Winnie" to ease his loneliness.
Rin graduates high school and returns to Australia to continue training with a multi-national team there. He begins working with Mikhail Makarovich Nitori, a former professional swimmer and current professional swimming coach. He meets and gets to know Natsuya Kirishima, who informs him that he should watch out not only for Haruka, but also his brother Ikuya, as rivals for swimming glory. Rin returns to Japan to participate in the All-Japan Invitational, a competition that determines who will move on to compete on the global level. Rin qualifies by winning the 100m butterfly event.
- Main article: Rin Matsuoka/Story
- Main article: Rin Matsuoka/Relationships
- Main article: Rin Matsuoka/Music
Creation and Conception
- Like all swimmers associated with the Iwatobi High School Swimming Club, Rin has a feminine name.
- Rin cannot sleep without his pillow.
- Haruka stated that Rin accidentally called his coach "mom" during elementary school.
- Gou has admitted that Rin shaves his body hair to reduce water resistance.
- Rin's best subjects are English and Math, while he's bad at Literature and Old Japanese.
- Rin's favorite food is meat; his least favorite is sweet food.
- Rin likes sports that he's good at doing.
- Rin's best stroke is the butterfly, but his obsession with beating Haruka (who usually swims freestyle), leads him to focus on that stroke and whatever distance Haruka is swimming in competition.
- In the same series, Akeno Watanabe (Rin's child voice actor) also voices his sister Gou Matsuoka.
- Rin inherited his shark-like teeth from his father.
- When younger, Rin would introduce himself to a group by pointing out his girly name, but saying he's a boy.
- Rin loves survival games.
- He has a pet cat named Steve.
- When they were kids, Rin slept together with Haru in his bed for a sleepover because he forgot his special pillow. (Duet/Drama CD)
- When Haruka is looking for a Tokyo apartment, Rin says, "Tell Haru it won’t matter when you are asleep."
- Big!Rin has more of a sense of humor than Little!Rin, but is still as sensitive as he was as a child and is likely to cry at movies or when he loses a race.
- Rin likes both cats and dogs though cats never seem to like him.
- He owns a diary.
- His motif animal is a shark.