About two hours
Apple Watch Series 6;系统:Watch OS7.2;
The charging law of Apple Watch smart Watch is exactly the same as that of mobile phone, when the power is less than 20%, the Apple Watch is charged, the first charge, the time is best to maintain more than five hours, because the first charge is very critical, which directly affects the service life of the future. In the future, you can be a little more casual, as long as you charge an hour or two.