Definition

Noun: * (Computing) The usable data storage capacity of a disk drive after formatting. This is the amount of space available to the user for storing files, calculated by subtracting the space taken up by the disk's structural data (like sector headers, boundary definitions, and timing information) from its total raw capacity.

Usage

• Formatted capacity is always less than a drive's total raw or unformatted capacity.
• This term is used when specifying the actual available storage of hard disk drives (HDDs), solid-state drives (SSDs), USB flash drives, and other storage media.
• It is the figure reported by operating systems (like Windows, macOS, Linux) in their file managers.

Examples

Advanced Usage

• The formatted capacity can vary slightly depending on the file system used (e.g., NTFS, FAT32, APFS, ext4), as each system manages disk space with different overheads.
• In professional data storage contexts, formatted capacity is a critical specification for calculating actual available storage in arrays and servers.

Variants and Related Words

• Unformatted Capacity (or Raw Capacity) (n): The total theoretical data storage potential of a disk drive before any file system structure is written.
• Format (v): The process of preparing a data storage device for initial use, which creates the file system and determines the formatted capacity.
• Usable Capacity (n): Often used synonymously with formatted capacity.
• Overhead (n): The portion of the disk's capacity consumed by the formatting process and file system management, which is not available for user data.

Synonyms

• Usable storage
• Net capacity
• Available capacity

Antonyms

• Unformatted capacity
• Raw capacity
• Theoretical capacity

Noun

1. (computer science) the usable capacity of a disk drive; the amount of space that is left after the sector headings and boundary definitions and timing information have been added by formatting the disk