Ranma1/2(Japanese: らんま1/2 Ranma nibun no ichi) is a comedy anime and manga by Rumiko Takahashi about a boy named Ranma Saotome who was trained from early childhood to age 16 in the martial arts, and who becomes a girl when splashed with cold water (and is turned back into a boy with warm water) due to a magic curse.

The manga was serialized in Japan in Shogakukan's Shonen Sunday where it ran from 1987 - 1996. Takahashi has stated in interviews that she wanted to produce a story that would be popular with children. Ranma's main audience were boys from elementary to junior high school age. In western fandom, the anime is sometimes criticized for creating some internal inconsistencies compared to the manga, which was less popular in the United States. Another major complaint is the animated series padding out the original story excessively and lacks a strong ending, though the series in North America tends to be much more analyzed (overly so, according to some) than in the East. Takahashi's subsequent anime, InuYasha, also arguably suffers from such overextension.

Ranma was extremely popular among American otaku in the 1990s, and popularized many of anime's most common visual gags. The infamous 'cursed water' plot device has even come up in anime-themed custom role playing games as a quick transgender device. In fact, the anatomical logistics of the cursed condition were purposely glossed over by Ranma's creator to avoid making it too complicated or a detraction from its comedic effect. See Pregnant Ranma Problem.

The manga is published in English by VIZ Media. The manga is flipped to the left-to-right format.

Story

Male and female Ranma SaotomeOn a training journey in the Byankala Mountain Range in the Qinghai Province of China, Ranma and his father, Genma Saotome, fell into the cursed springs at Jusenkyo (Loosely translated, it means Springs of Sorrow). Each spring is associated with a story about someone or something that drowned in it hundreds or thousands of years ago, and anyone who falls in a spring is cursed to turn into whatever drowned in that spring whenever they come in contact with cold water, although they keep their original minds, personalities and skills in the new form; hot water reverts the cursed to their original form. Genma fell into the Spring of the Drowned Giant Panda, and Ranma fell in to the Spring of the Drowned Girl.

Upon returning to Japan, Genma informs Ranma that he's been engaged to a girl that he has never met when only a few blocks away from that girl's house. At the same time, Soun Tendo tells his three daughters that one of them is to marry Ranma (whom they've never even heard of) in order that the Tendo dojo might be carried on. When they first meet Ranma, they see him in his female form. This caused some confusion until Akane sees Ranma in his male form (After walking in on him in the bath) and finds out that he becomes a she upon application of cold water, the two older sisters push the engagement on the youngest sister, Akane, since she "hates boys (due to the rude ways they treat her at school), and Ranma is half girl;" thus begins the love/hate relationship between Ranma and Akane that lasts for the rest of the series.

This, combined with multiple suitors for both Ranma and Akane, many strange forms of martial arts, and the various curses of many of the cast members makes this a bizarre series.

Ranma has been extremely popular in anime fandom since the early-middle 1990s, and for many was their introductory series. An enormous amount of fanfiction exists for the series — mostly due to the ease of writing in stories, and the quirky characters who allow for a lot of creative freedom; fictional crossovers in particular — potentially more so than any other anime popular in the United States.

The majority of fanon for the series is infamous for being notoriously unreliable and sometimes outright contradicting plot points, albeit obscure at times and contradicting the original comic version.