Original micro TF SD Card 256GB 128GB 64GB 32GB TF Class 10 UHS-1 Memory Card Flash Card Memory micro for Smartphone PC

4GB=approximately 3.5GB-3.7GB

8GB=approximately 7GB-7.3GB

16GB=approximately 14GB-15GB

32GB=approximately 28GB-30GB

64GB=approximately 58GB-60GB

128GB=approximately 119GB-120GB

256GB=approximately 230GB-238GB

Vendors are using Flash memory decimal arithmetic: 1 MB = 1000KB, 1G = 1000 MB

Calculated, operating system with binary arithmetic: 1 MB = 1024KB, 1 GB = 1024 MB;

This is calculation difference between manufacturer and our PC,just for you reference.