Toilets in Japan are sometimes designed more elaborately than toilets commonly seen in other developed nations. European toilets occasionally have a separate bidet whilst Japan combines an electronic bidet with the toilet. The current state of the art for Western-style toilets in Japan is the bidet toilet, which as of March 2016 is installed in 81% of Japanese households. In Japan, these bidets are commonly called washlets, a brand name of Toto Ltd., and they may include many advanced features rarely seen outside of Asia. The basic feature set commonly found on washlets consists of anal hygiene, bidet washing, seat warming, and deodorization.

A bidet is a bowl or receptacle designed to be sat upon in order to wash a person's genitalia, perineum (taint), inner buttocks, and anus. The modern variety has a plumbed-in water supply and a drainage opening, and is thus a plumbing fixture subject to local hygiene regulations. The bidet is designed to promote personal hygiene and is used after defecation, and before and after sexual intercourse. It can also be used to wash feet, with or without filling it up with water. In several European countries, a bidet is now required by law to be present in every bathroom containing a toilet bowl. It was originally located in the bedroom, near the chamber-pot and the marital bed, but in modern times is located near the toilet bowl in the bathroom. Fixtures that combine a toilet seat with a washing facility include the electronic bidet.