Although known by its official name Shin Shin Toitsu Aikido (心身統一合気道) - "aikido with mind and body unified" it is frequently referred to as Ki-Aikido. Another name used is Shin Shin Toitsu Aikido Kai.
According to it's own sources, there are currently about 30 000 Japanese members and about 100 000 members overseas in 21 countries. These figures are not including Kenjiro Yoshigasaki sensei organisation, Ki no Kenkyukai Association Internationale, which earlier was a part of the European Shin Shin Toitsu Aikido but broke away in 2003.
The term "Ki-Aikido" is also used for other styles developed by Tohei's students, like Aikido Yuishinkai by Koretoshi Maruyama.