A heat map is a type of visualisation tool that uses colours to demonstrate data values' relative intensity. In UX design, heat maps show where users click, tap, or scroll on a website. Areas with the most user engagement appear as "hotter" (or have a brighter colour), whereas areas with the least user engagement are "cooler" (or have a darker colour).
A heat map is a valuable tool for UX designers and researchers. The format easily explains how users interact with a digital product. Heat maps also help find usability issues and ensure that design decisions are data-driven. For example, if there's a website component that users try to click on despite it being non-interactive, designers can adjust their design and enable users to interact with the component. As a result, by working with heat maps, designers can improve the user experience of a product, leading to higher user engagement.
Finally, heat maps are a fairly low-cost research method. This means that even smaller businesses or startups can use them to gather data on the interaction between the user and a product.
If you want to use heat maps, get the most out of them. Start by using multiple types of heat maps. There are separate maps for different user actions, such as scrolling or clicking – make sure you're using each and every one that can help you optimise the user experience. You should also consider combining heat maps with other research methods, such as user testing, surveys, or analytics. You'll then get a comprehensive picture of your users' behaviour. Only by having the complete picture can you ensure that your design decisions remain informed. And don't forget to test and iterate: if a heat map shows a usability issue, fix it, and test it again. Even once you've reached the optimal user experience, test your designs regularly to stay up-to-date with your users' needs.
To fully capitalise on heat maps, you should also steer clear of certain things. As mentioned, relying only on heat maps will not get you the full context you're looking for regarding user needs and preferences. You shouldn't shy away from combining it with other methods; especially, you shouldn't overlook qualitative data. Qualitative data can give context to the quantitative data from the heat maps. This is something that you won't get from just quantitative research methods.
Finally, don't make assumptions without testing. Once you modify the designs according to the heat maps results, test them again to see whether they actually improved user experience. Don't implement anything without testing it first.
Heat maps are just one of many tools in the UX researcher's arsenal. Collected data enables UX designers to make data-driven decisions that actually enhance user experience. But keep in mind that, much like other research methods, heat maps work best if they're combined with other types of UX research methods.