The most spoken languages

 1. Chinese, (Mandarin)

Spoken in Brunei, Cambodia, China, Indonesia, Malaysia, Mongolia, Philippines, Singapore, South Africa, Taiwan, Thailand

Spoken by 885 million people

 2. Spanish

Spoken in Andorra, Argentina, Belize, Bolivia, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, Spain, Uruguay, United States,Venezuela

Spoken by 332 million people

 3. English

Spoken in Australia, Botswana, Brunei, Cameroon, Canada, Eritrea, Ethiopia, Fiji, Gambia, Guyana, India, Ireland, Israel, Lesotho, Liberia, Malaysia, Micronesia, Namibia, Nauru, New Zealand, Palau, Papua New Guinea, Samoa, Seychelles, Sierra Leone, Singapore, Solomon Islands, South Africa, Suriname, Swaziland, Tonga, United Kingdom, United states, Vanuatu, Zimbabwe

Spoken by 322 million people.

 4. Bengali

Spoken in Bangladesh, India, Singapore

Spoken by 189 million people

 5. Hindi

Spoken in India, Nepal, Singapore, South Africa, Uganda

Spoken by 182 million people

 6. Portuguese

Spoken in Angola, Brazil, Cape Verde, France, Guinea-Bissau, Mozambique, Portugal

Spoken by 170 million people

 7. Russian

Spoken in China, Israel, Mongolia, Russia

Spoken by 170 million people

 8. Japanese

Spoken in Japan, Singapore, Taiwan

Spoken by 125 million people

 9. German

Spoken in Austria, Belgium, Bolivia, Germany, Hungary, Liechtenstein, Luxembourg, Paraguay, Poland, Romania, Slovakia, Switzerland

Spoken by 98 million people.

10. Chinese, (Wu)

Spoken in China

Spoken by 77.2 million people.

  1. Javanese - 75.5 million people
  2. Korean - 75.0 million people
  3. French - 72.0 million people
  4. Vietnamese - 67.7 million people
  5. Telugu - 66.0 million people
  6. Marathi - 64.8 million people
  7. Tamil - 63.1 million people
  8. Turkish - 59.0 million people
  9. Urdu - 58.0 million people
  10. Chinese, (Min Nan) - 49.0 million people
  11. Chinese, (Jinyu) - 45.0 million people
  12. Gujarati - 44.0 million people
  13. Polish - 44.0 million people
  14. Arabic - 42.5 million people
  15. Ukrainian - 41.0 million people
  16. Italian - 37.0 million people
  17. Chinese (Xiang) - 36.0 million people
  18. Malayalam - 34.0 million people
  19. Chinese, (Hakka) - 34.0 million people
  20. Kannada - 33.8 million people

The next few languages in line include western and eastern Panjabi, Sunda, Romanian, Bhojpuri, Azerbaijani, Hausa, Algerian Arabic, Burmese, Serbo-Croatian, Awadhi, Thai and Dutch

this list was made by doing extensive database and spreadsheet work, with a variety of original sources, but mainly an Introduction to Linguistics textbook, and an ethnology database made by one of the professors at my former university. Enjoy!