Most of these watches need to be recharged every so often, but they all differ in the number of days that the charge will hold. We do have this information for each product in the summary when it was provided by the manufacturer. Some of them can go as long as a week or so before the battery needs a boost, but in general, the battery life and charge will depend heavily on the usage amount of the watch by the wearer. As more functions are accessed and utilized, the battery will decline much faster.