What company does Google belong to?

Google is a subsidiary of Alphabet.

/kloc-in August of 0/5, Google announced that it would adjust its corporate structure and separate search, YouTube and other online subsidiaries from the R&D investment department by establishing an "umbrella company" called Alphabet.

Alphabet will replace Google's listing on Nasdaq, and all Google's current shares will be automatically converted into Alphabet shares with the same number and rights. The new Google will become a subsidiary of Alphabet, covering the search business, YouTube, Android and Chrome operating systems.