Which language has the largest number of speaker in world?

The language with the largest number of speakers in the world is Mandarin Chinese.

It's important to note that "speakers" can be defined in different ways, which can affect the rankings. Some sources include all varieties of Chinese, while others focus only on Mandarin.

Here are some estimates:

* Over 1 billion speakers of Mandarin Chinese, including all varieties.

* Around 939 million speakers of Mandarin Chinese specifically, according to Ethnologue.

This makes Mandarin Chinese by far the most spoken language globally.