According to this report, these are the most searched abbreviations, by average monthly searches.
1. SMH (shaking my head) . . . 231,000
2. POV (point of view) . . . 156,000
3. NSFW (not safe for work) . . . 127,000
4. FOMO (fear of missing out) . . . 122,000
5. TLDR (too long; didn’t read) . . . 119,000
6. IYKYK (if you know, you know) . . . 99,000
7. OFC (of course) . . . 96,000
8. IMO (in my opinion) . . . 75,000
9. IIRC (if I recall correctly) . . . 66,000
10. HMU (hit me up) . . . 64,000
11. LMAO (laughing my [butt] off) . . . 64,000
12. AFK (away from keyboard) . . . 59,000
13. NGL (not gonna lie) . . . 59,000
14. OOTD (outfit of the day) . . . 56,000
15. IG (I guess) . . . 54,000
16. TBH (to be honest) . . . 51,000
17. TTYL (talk to you later) . . . 51,000
18. DM (direct message) . . . 47,000
19. YOLO (you only live once) . . . 47,000
20. FWIW (for what it’s worth) . . . 44,000