A dash cam’s recording capacity depends on a few different factors, like the size of the memory card and whether the camera is battery-powered or wired to your vehicle. Wired cameras can record continuously, turning on and capturing video any time your car is running. Battery-powered models will be limited. However, your memory card also determines how long your camera can record before it begins looping or recording over any older video footage. For example, a 128 GB memory card can get up to 18 hours while a 16 GB version will capture only three hours.