/ˈmɑːstər faɪl ˈteɪbəl/
noun — "central table of file metadata."
Master File Table (MFT) is the core metadata repository used by the NTFS file system to manage all files and directories on a storage volume. Each file, directory, or system object has a corresponding MFT entry containing critical information, including file name, security descriptors, timestamps, attributes, data location pointers, and size. The MFT allows NTFS to efficiently locate, read, and modify files while maintaining data integrity, access control, and journaling consistency.
Technically, an MFT entry is a structured record typically 1 kilobyte in size. Small files may store their contents directly within the MFT entry, called resident files, while larger files use non-resident entries that point to clusters on the disk where the actual data resides. Attributes include standard information (timestamps, permissions), filename attributes (long names, multiple names), security descriptors for access control, and optional extended attributes. NTFS also maintains special MFT entries for the volume itself, the bitmap tracking free clusters, and the log file for journaling purposes.
In workflow terms, consider creating a document in Windows. NTFS allocates an MFT entry for the file, updates the directory listing, and records the allocated clusters in the entry. Reading the file involves querying the MFT to locate its clusters and applying access controls before retrieving data. Operations such as moving, renaming, or deleting a file are performed by updating the MFT entries, minimizing disk movement and supporting fast metadata access.
A simplified pseudocode example of MFT interaction:
// Pseudocode illustrating MFT entry lookup
entry = MFT.getEntry("C:\\Documents\\report.txt")
if entry.exists():
data = readClusters(entry.clusterPointers)
print(data)
MFT also interacts closely with the NTFS journaling system. Changes to entries are logged before committing to the disk to enable recovery in case of system crashes, ensuring ACID-like durability for metadata. Because the MFT is central to all file operations, it is typically stored in a reserved area at the beginning of the volume and may include a mirror copy for redundancy.
Conceptually, the Master File Table is like a library’s main card catalog: each card (MFT entry) contains not just the book’s title but its physical shelf location, borrowing rules, and historical notes, allowing librarians to quickly locate, track, and manage every book efficiently.
See NTFS, Journaling, FileSystem.