There were 2.3 billion internet users (2,279,709,629) worldwide in the first quarter of 2012, according to Internet World Stats data updated 31st March 2012. China was the largest countries in terms of internet users with over 513 million users.

Top 20 internet countries worldwide in Q1 2012
1. China: 513.1 million
2. US: 245.2 million
3. India: 121.0 million
4. Japan: 101.2 million
5. Brazil: 81.8 million
6. Germany: 67.4 million
7. Russia: 61.5 million
8. Indonesia: 55.0 million
9. UK: 52.7 million
10. France: 50.3 million
11. Nigeria: 45.0 million
12. Mexico: 42.0 million
13. South Korea: 40.3 million
14. Iran: 36.5 million
15. Turkey: 36.4 million
16. Italy: 35.8 million
17. Philippines: 33.6 million
18. Vietnam: 30.9 million
19. Spain: 30.7 million
20. Pakistan: 29.1 million