AdSense RPM Dropped 40% After Switching to 4K Videos – Is This Normal?

That's a huge drop, and I've seen this happen on my own channel when I experimented with 4K. One major factor is that 4K videos often have longer load times and higher bandwidth consumption, which can lead to lower ad completion rates – some viewers may skip ads or abandon the video before the ad finishes. Also, YouTube's ad system might be categorizing your content differently if the metadata or audience retention changes.

Check your Audience Retention graph for the 4K videos vs. your old 1080p ones. If retention is lower in the first 30 seconds, that could be hurting your ad impressions. Also, look at your CPM by geographic region – 4K might be attracting more viewers from countries with lower CPMs. I'd suggest using YouTube Studio's "Revenue" tab to compare the last 28 days before and after the switch, filtering by video resolution. If the trend holds, consider uploading in 1080p but upscaling to 4K for the visual quality, or at least test a few 4K videos with different ad settings (e.g., mid-roll placement) to see if that helps.

That was spot on – I dug into my analytics and found that my 4K videos had a 15% lower retention in the first 30 seconds, likely because the larger file sizes caused buffering for some viewers. I also noticed that my CPM from the US dropped, but my traffic from India and Brazil increased, which explains the RPM drop. I've switched back to 1080p for now, but I'm keeping the 4K versions for select videos and using mid-roll ads more strategically. The RPM is back up to $11.80, and views are still stable. Thanks for the help!