The answer is 48. The 2 that are commonly disputed are Russia and Turkey as they both are counted among Europe and Asia. If you count Cyprus, the Philippines and Hong Kong, there are 51.
The following are the 46 definite countries of Asia:
1. Kuwait
2. Mongolia
3. China
4. India
5. Sri Lanka
6. Maldives
7. Nepal
8. Bhutan
9. Bangladesh
10. Myanmar
11. Thailand
12. Laos
13. Vietnam
14. Cambodia
15. Indonesia
16. Malaysia
17. Timor Leste
18. Brunei
19. Singapore
20. Taiwan
21. Philippines
22. Japan
23. North Korea
24. South Korea
25. Pakistan
26. Afghanistan
27. Tajikistan
28. Kyrgyzstan
29. Kazakhstan
30. Uzbekistan
31. Turkmenistan
32. Georgia
33. Armenia
34. Azerbaijan
35. Iran
36. Iraq
37. Syria
38. Lebanon
39. Jordan
40. Israel
41. Saudi Arabia
42. Yemen
43. Oman
44. UAE (United Arab Emirates)
45. Qatar
46. Bahrain
And then there are the debatable ones. 47. Hong Kong 48. Turkey 49. Russia 50. Cyprus 51. Philippines
Australia, New Zealand, Papua New Guinea, Palau, Nauru, Tuvalu, Kiribati, Vanuatu, Samoa, Fiji, Tonga, Micronesia, the Marshall Islands and the Solomon Islands are all located in Oceania.
Egypt is not Asia. Today the Middle East is classified as Asia, but was always considered Northeast Africa in the times before the Crusades and the construction of the Suez Canal. 100