About REAL Capacity：
16GB = approximately 14GB-15GB
32GB = approximately 28GB-30GB
64GB = approximately 58GB-60GB
128GB = approximately 119GB-120GB
This is calculation difference between manufacturer and your PC, please Google ‘Memory card capacity’ to get more information.
For your reference
Your PC says 1GB = 1.073741824 Billion bytes where Market Defines 1 GB = 1.00 Billion bytes.
TECH SPECS： Product Type :USB 3.0 Flash Drive Application: PC, Notebook Capacity :32GB/64GB/128GB (1GB=1Billion byte) * Actual usable capacity may be less (due to formatting, operating system, applications or otherwise) Interface: USB 3.0 Connector :Standard A Dimension (WxHxD) :40 X 12.2 X 10.92mm Weight: Approx. 9.9g Speed: Up to 130MB/s transfer speed * Actual speed may vary depending on use host device conditions and environment.,write speed will be a little lower.