To measure your wrist, use the factory Sport band that comes with your Apple Watch.
Simply follow the steps that correspond with the circled numbers labeled on the illustration below.
Step 1: Determine which size Apple Sport band you use, either S/M or M/L. The size is located on the underside of your Sport band.
Step 2: Find the hole you use most often on the illustration below.
Step 3: The hole you use will point to your exact Spark*l size. That's it!
For Example: If you use the 4th hole on the S/M Apple Watch Sport band, you would be an XS in Spark*l sizing. If you have any questions, about custom sizes, using different Smart Watches, or anything else, feel free to contact us!