A scroll map is a colour-coded picture of a web page that shows what share of visitors scrolled down to each point. The top is usually red or orange, where nearly everyone sees the content, cooling to blue further down, where only a few people ever reach.
How a scroll map works
Behaviour analytics tools such as Hotjar and Microsoft Clarity add a script to your pages that records how far each visitor scrolls. The tool combines those records for one page and paints them over a screenshot, with a percentage at each line: “80% of visitors reached this point”, “35% reached this point”. Most tools also mark the average fold, the line where the screen ended before anyone scrolled.
A scroll map is one type of heatmap. Click maps show where people tap or click; scroll maps show how far they get. Results are split by device, and they need to be, because the same page can be twice as long on a phone as on a laptop.
The picture is only as good as its sample. A few dozen page views produce a jagged, unreliable map, so wait until a page has had a few hundred views on each device before reading much into it.
Why it matters
Most pages lose readers steadily as they go down, and that is normal. What a scroll map exposes is where they leave suddenly, and what sits below that point. If your prices, reviews or enquiry form sit below a band where most mobile visitors have already gone, they are close to invisible, however good they are.
Scroll maps also reveal “false bottoms”: a full-width banner, a large gap or a footer-like block that makes the page look finished when it is not. A sharp colour change just under such an element is the giveaway.
In the UK, these tools usually need consent. They store data on the visitor’s device and record behaviour, so under PECR they normally sit behind analytics consent on your cookie banner, and under UK GDPR you should mask form fields so personal details are never captured. That also means the map shows the behaviour of visitors who accepted, which is a subset of everyone.
Common mistakes
- Treating any drop-off as a problem. Every page loses readers; look for steep cliffs, not gentle slopes.
- Reading the desktop map and redesigning the mobile page from it.
- Cramming everything into the first screen, which makes the top of the page cluttered and harder to act on. Content above the fold should say what the page is and what to do next, not hold everything.
- Ignoring elements that change page length, such as cookie banners, accordions and sliders, which can distort the map.
- Drawing conclusions from very few page views.
How to act on it
Pick your most important pages, usually those receiving paid traffic or the most organic visits, and read the mobile scroll map first. Find the steepest fall and look at what sits just above it: a weak section, a false bottom or a block of text nobody needs. Then move the content that drives action higher, cut what does not help, and remove anything that looks like the end of the page.
Check the result against watched session recordings to see the behaviour behind the colours, and against enquiry or sales figures to confirm the change helped. Reading scroll maps and reworking pages around them is part of how I build and improve landing pages for Google and Facebook ads.