How many species of animals are there?

As of 2011, there were an estimated 7.77 million species of animals on Earth, encompassing all phylums and families in the animal kingdom. This number increases to 8.74 million if non-animal species from the plant, fungi, protozoa and protist kingdoms are included.

Less than 1 million of the estimated 7.77 million species were officially cataloged in 2011, and only 1.2 million species were cataloged across all five kingdoms. The Census of Marine Life predicts that 86 percent of all land species and 91 percent of all water species are yet to be discovered, as the majority of tiny life forms are still unknown.