Sensor Type

A is a type of ninja who is capable of detecting the presence of other people through their chakra. A skilled sensor can detect their targets from a great distance, as well as differentiate the characters by their signature chakra alone. Such examples include Karin being able to tell exactly who is among a crowd of people, and Fū being able to tell that a sensor type is amongst a group of four strangers. Karin is good enough to tell if her targets are lying based on any fluctuating chakra. According to Karin, in the Anime, Sensor types vary between the Hidden Villages, (i.e. the Ninken of the Inuzuka clan can smell chakra.)

Karin's sensing abilities are derived from her Mind's Eye of the Kagura; it is unknown if other sensors also have a specific jutsu to do so, or if it is a general skill.

Sages, who utilize natural energy, can also detect presence of people through their chakra, making them somewhat like sensors. Kisame Hoshigaki's blade, the Samehada, is attracted to intense chakra, allowing him to hunt down such individuals.