To find out what size battery fits a watch, look for the battery identification number, refer to the owner’s manual, and check the numbers indicated on the battery itself. The exact method to find the correct battery size depends on the watch’s make and model.
The simplest way to find the appropriate watch battery size is to look for the battery identification number, usually indicated on the back of the watch. If no number appears on the back, check for the battery size required for the watch in the user’s manual. Watch manuals are available online by searching the model number and brand name. Lastly, the numbers printed on the battery itself may indicate its size. To access the watch battery, remove the back cover by gently prying it off using a knife.