Formatted Storage Capacity Information

Formatted Storage Capacity Information

The storage capacity of a storage device (as reported by many operating systems) may be different than the capacity that is listed on its label.

Data storage products (including USB flash drives, memory cards, and hard drives) include the total capacity, at an unformatted level, that is stated on the product or the product packaging. For example, a 128GB USB flash drive has a total capacity of 128,000,000,000 bytes at the unformatted level (where 1GB = 1,000,000,000 bytes).

Definitions of a Megabyte:

• Operating Systems commonly define capacity as follows:
• Kilobyte (KB) as: 2 to the 10th power (1,024 bytes)
• Megabyte (MB) as: 2 to the 20th power (1,024 X 1,024 bytes = 1,048,576 bytes)
• Gigabyte (GB) as: 2 to the 30th power (1,024 X 1,024 X 1,024 bytes = 1,073,741,824 bytes)
   
• Disk drive and flash memory card manufacturers commonly define a MB as one million bytes (exactly 1,000,000 bytes) and a GB as one billion bytes (exactly 1,000,000,000 bytes).

Storage device manufacturers define 1 GB as 1,000,000,000 bytes.
Operating systems typically define 1 GB as 1,073,741,824 bytes.

Note: Some capacity is used for formatting and other functions and thus not available for data storage. A portion of the total capacity is used to store certain functions including optimizations of the memory that support performance and endurance and therefore is not available for user storage.