What is the size of a protazoin?

Protozoa are generally unicellular organisms and vary significantly in size. They typically range from about 1 micrometer to several millimeters in length, depending on the species. For example, the common amoeba can be around 0.5 to 1 millimeter, while other protozoa, like certain ciliates, can be much larger. Overall, their size allows them to be observed under a light microscope.