Facebook today is changing how it ranks the videos that appear in the News Feed, with the goal of better surfacing those that are more relevant to you. It’s a slight tweak, but one that could boost the visibility of longer videos, in some cases.

It can be more of commitment to watch a longer video in full, of course – the content has to be interesting enough to keep your attention. Now, long videos that people are actually watching may be distributed more on Facebook.

The company explains that “percent completion” – how much of a video is watched – is still just one of the signals it uses to determine which videos should show up in your News Feed. It also takes into account a number of other factors, like if you turn on the sound, go fullscreen, turn on high-def, among other things. And it considers whether or not a video is live.

However, the percent completion signal needed an adjustment, Facebook found. After all, it’s a lot easier to watch a shorter video all the way through, compared with a long one. That’s why it makes sense to weight this percent completion signal a bit more, the longer the video is.

However, this change won’t only impact those videos that get watched to the end. It will also affect longer videos that people are watching in general, even if they’re not completing them.

For example, before, if people were watching 75 percent of a 2 minute video, that was ranked the same as watching 75 percent of a 10 minute video. Obviously, that’s not really fair. Now, the algorithm will put more weight on completing that longer video.

This includes Facebook Live videos that were recorded earlier, and have now transitioned to regular videos. In addition, the algorithm will apply not just to those videos on the News Feed itself, but also in the Suggested Videos section which appears below the one you’re currently viewing.

For Facebook Page owners, the takeaway here is that longer videos that engage users may get a bump up in terms of distribution, but the side effect could mean that some shorter videos see a small dip, Facebook confirms.

There’s no set length on what makes a video “long,” however.

As Facebook explains in its announcement, “the best length for a video is whatever length is required to tell a compelling story that engages people, which is likely to vary depending on the story you’re telling.”

Facebook also recommends that Page owners utilize the video insights section in their Page Analytics in order to understand what works best for their particular audience.

The change is not immediate, but is rather rolling out gradually over the next few weeks.