Welcome to our new blog! To kick things off, we're starting with a practical guide to one of the most common questions Casio and G-Shock owners have: Which battery does my watch use?

The good news is that it's surprisingly easy to identify your watch model and find the correct battery. Throughout this guide, we'll refer to both G-Shock and Casio watches simply as Casio, since G-Shock is a collection under the Casio brand.

On most Casio watches, you'll find both the model number and the module number engraved on the case back. These markings make it easy to identify your watch and determine the correct battery. We've also included Casio's official battery reference to help you find the right replacement if you decide to change the battery yourself at home.

If you'd rather leave it to the professionals, feel free to bring your watch into our store—we'd be happy to replace the battery for you.

In the photos below, we've highlighted two examples showing where to find the model number and module number. The model number typically begins with letters followed by numbers, making it easy to distinguish from the module number.

For the dedicated Casio enthusiasts, we're also considering a future post explaining Casio's model naming and nomenclature system. Stay tuned for more watch tips, guides, and interesting content. If there's a topic you'd like us to cover, let us know in the comments or reach out to us on social media—we'd love to hear your suggestions!

This example shows the popular G-Shock "CasiOak" **GA-2100A-8** model, equipped with the **Module 5711** quartz movement, both clearly engraved on the case back for easy identification.

In this example, you can easily identify the **A158WE** model number along with its **Module 593**, both engraved on the case back for quick reference.

Click here to access the watch battery guide. Please note that not every Casio model is included in the reference.