Scroll behavior across the web

August 12th, 2013 by Josh

You might’ve come across our graphic on Engaged Time below the fold at some point in the last few months in AdAgeBuzzfeed, or on the blog. That figure's message is simple: even if not every reader scrolls down the page, the vast majority of readers’ collective time is spent below the fold (the typical height of a browser window, about 700 pixels), which has traditionally been an undervalued part of most sites.

I wanted to take a closer look at what goes into generating this effect, so I gathered a random sample of 25 million user sessions from across a wide sample of sites and content types and took a look at where these users spent their time reading.

(Important disclaimer: some of our customers don't allow us to anonymously aggregate their data; as always, the data presented is drawn from those who do).

Scroll depth

Let’s start with the basics — the breakdown of where readers scroll on a typical site. Below you’ll see data showing the fraction of users who actually viewed each part of the page. For instance, we see that just under 70% of visitors saw the very top of the page they were viewing.

Scroll depth

There are a few notable trends:

  1. Many visitors scroll down the page before it finishes loading, which means that no portion of a typical article is viewed by 100% of viewers and the very top of the top of the page actually has about a 20% lower view rate than slightly farther down.

  2. The most viewed area of the page is just above the fold, at about 550 pixels, with just over 80% viewership.

  3. From this peak at 550 pixels, there is a slow decay in viewership. About 50% of readers see 1500 pixels down the page on content pages, while on home pages and section fronts 50% of readers make it to pixel 1000.

Scroll engagement

On the other hand, because much of an article’s actual content is downpage, those readers who do scroll down spend much more time down the page than they do at the top. We see this represented in the next figure, where we show the amount of time each area of the page was actively viewed by those who actually scrolled to view it at all.

Engagement across the page

Pixels at the top of the page are in view for the shortest amount of time — about 4 seconds — and the amount of time in view steadily rises as we move downpage to a peak between about 1200 pixels down. This portion of the page is viewed for nearly three times as long as the top of the page.

Expected time in view

To look at the tradeoff between these two metrics — viewership and time — let’s take a look at the joint distribution of the two. The graphs below show the expected amount of time that a visitor will view each part of the page for — the product of the percentage of people who view part of a page with the time that viewers spend there.

Expected engaged time

So, which portions of the page have the potential for the highest impact on your audience? That depends on your goals, of course. Two goals we hear frequently are maximizing reach and maximizing exposure time. If the former, it appears that placing it just above the fold is the best possible bet. On the other hand, if you want to maximize the amount of time that viewers spend with it in view — a good goal for brand advertisements and site modules that take time to consume — a placement around 1200px may be better. And, if you want to maximize the tradeoff between the two, positions slightly below the fold between 600 and 1000 pixels typically have both high viewership and high engagement.

Of course, it should go without saying that all of this data is presented in aggregate, and the scroll patterns of your site’s audience may be quite different.

  • http://blogrank.cytrap.eu/ig/4yt/*/*/*/CEO/top100 Urs E. Gattiker

    HMMMM Very interesting blog post

    I thought it particularly interesting that it confirms previous work about how people leave a webpage within the first few seconds
    ==== http://www.flickr.com/photos/measure-for-impact/6144860226/ (ACM Communication – articles)

    You also point out that people do not scroll down. Hence my question:
    Considering your findings, does this blog address this by focusing on maximizing reach (putting all above the fold) or just below the fold (maximize time spent by readers)?

    Considering your wide header, I would guess you go for point 1 – maximizing reach?

    Josh, can you help me out please? Merci bien for your answer.

    Urs E. Gattiker from CyTRAP Blog Rank – Chartbeat Blog GREAT (click to get data)

    • Josh Schwartz

      I’d say in my own writing I’m focused on putting information where users will spend the most time, and I’m spending very little effort on getting information above the fold.

      • http://blogrank.cytrap.eu/ig/4yt/*/*/*/CEO/top100 Urs E. Gattiker

        Thanks @disqus_IGB7LLo8Pw:disqus for your very helpful answer.
        So the trick is just to get them to read beyond the “above fold” Of course, then we have to provide them with the ‘value’.
        But this also means than maybe 50 percent or more will never get to the gems of the story.
        That is too bad.
        Merci
        Urs @ComMetrics:twitter
        PS. I must admit based on your numbers and others (see my comment above with link) I have started to worry about the first 60 words (i.e. are they easy to grasp, lay out what will be discused in telegram style, etc.).
        Our numbers also show it matters for the CyTRAP Blog Rank and Google – (click to get data)
        We explain it here: 1st Impression matters if you want people to read on (click to read).

  • http://MediaArmory.com/ FidelGonzales

    Above the fold is the fluff. Below the fold is the stuff. An eye-catching CTA is summarizes the theme up top. The depth is delivered down low for full immersion. Thank you for sharing the outstanding insight.