On closer inspection of the full resolution map, you can see that even when broken down by dialect, Chinese is massive. At 848 million speakers, Mandarin outstrips English by half a billion.
"Smaller" dialects like Wu and Cantonese outstrip the entire population of Persian and Malay speakers.
The image is further broken down by country. The smaller areas within each language show the number of speakers in different countries.
Although the countries for each language are not comprehensive—countries with small numbers of speakers of that language are grouped together under a single area marked with "+"—the number of smaller areas gives a good picture of nationality and language at a glance. Arabic is spoken in a large number of countries, while Japanese is only spoken in Japan. Nearly half of Bengali speakers live in India.
The colors show which regions the countries are in using the following coding:
The coloring shows that languages like Spanish and English have wider geographic distribution than other large languages. With the exception of French, colonial languages like Spanish, English, and Portuguese have many more speakers in the new world than they have in their countries of origin.