All of the following statistics are from Human Rights Watch.
It should also be noted that in some of these countries these are very old laws and some are enforced more strictly than others. In most of these places there is still a robust gay community fighting for equality, so this isn't a plea to stop visiting these places! This list is just documenting where homosexual acts are technically illegal. Go to Human Rights Watch to read more about the specifics!
1. Algeria
2. Antigua & Barbuda
3. Bangladesh
4. Barbados
5. Bhutan
6. Botswana
7. Brunei
8. Burundi
9. Cameroon
10. Chad
11. Comoros
12. The Cook Islands
13. Dominica
14. Egypt
15. Eritrea
16. Eswatini
17. Ethiopia
18. Gambia
19. Ghana
20. Grenada
21. Guinea
22. Guyana
23. Iran
24. Jamaica
25. Kenya
26. Kiribati
27. Kuwait
28. Lebanon
29. Liberia
30. Libya
31. Malawi
32. Malaysia
33. Maldives
34. Mauritania
35. Mauritius
36. Morocco
37. Myanmar (Burma)
38. Namibia
39. Nigeria
40. Occupied Palestinian territory, Gaza Strip
41. Oman
42. Pakistan
43. Papua New Guinea
44. Qatar
45. Saint Kitts and Nevis
46. Saint Lucia
47. Saint Vincent and The Grenadines
48. Samoa
49. Saudi Arabia
50. Senegal
51. Sierra Leone
52. Singapore
53. Solomon Islands
54. Somalia
55. South Sudan
56. Sri Lanka
57. Sudan
58. Syria
59. Tanzania
60. Togo
61. Tonga
62. Tunisia
63. Turkmenistan
64. Tuvalu
65. Uganda
66. United Arab Emirates
67. Uzbekistan
68. Yemen
69. Zambia
70. Zimbabwe
Again, thanks to Human Rights Watch for this information. And here's another map from the ILGA.
Correction: Some of the wording has been changed, see the blurb in the beginning. Some of the pictures have also been replaced.