How much data does Google Maps use? Not much.
The short answer
Google Maps doesn’t use much mobile data at all when navigating. In our experiments, it’s about 5 MB per hour of driving.
Zooming in and out of the map doesn’t use as much data as one might suspect it would. Most of Google Maps data use is incurred when initially searching for the destination and charting a course, which you can do on Wi-Fi. Besides that, there are ways to ensure Google Maps doesn’t use any mobile data at all when driving.