Why do we not need defragmenting anymore?

Defragmenting, also known as defragging, was once an essential maintenance task for computers. It involved reorganizing files on your hard drive so that the data would be contiguous, allowing for faster read and write times. However, advancements in hardware and software have rendered defragmenting largely obsolete. Here’s why we don’t need to defrag as much these days.

Faster and more efficient file systems

Older file systems like FAT32 were prone to fragmentation over time as files were written, deleted, and rewritten. This would lead to data being scattered across different areas of the hard drive. Newer file systems like NTFS and HFS+ are much more resistant to fragmentation in normal use. They utilize techniques like preallocation to reduce file fragmentation. The way they structure and store file metadata also results in less fragmentation.


NTFS, introduced in Windows NT in 1993, uses a technique called Master File Table (MFT) to store metadata about files and folders on a volume. Each file and folder on an NTFS volume has a unique entry in the MFT which points to the actual data. This makes looking up file information very fast. The metadata is also stored contiguously rather than scattered around, minimizing fragmentation.


Apple’s HFS+ file system also uses a Catalog File that stores file metadata separately from the actual file data. Small files are stored directly in the Catalog File while larger files have their data stored elsewhere and referenced via pointers. This separation of metadata and file data reduces fragmentation.

Improved storage hardware

Advances in storage hardware also make defragmentation less necessary. Modern hard drives and SSDs are highly optimized to handle fragmented data:

  • Larger cache buffers – Disk caching allows drives to read large chunks of contiguous data into cache and write it out later in smaller fragmented pieces. This minimizes the impact of file fragmentation.
  • Faster sequential read/write – Drive heads can quickly scan across the physical sectors, assembling fragmented data into contiguous logical blocks.
  • Dedicated controllers – Sophisticated drive controllers can efficiently reorder and rewrite scattered data.

Solid state drives (SSDs) in particular have made a huge impact. With no moving parts, SSDs can access any data instantly without seek time delays. This makes the actual physical location of data irrelevant.

Built-in optimization in operating systems

Modern operating systems have baked-in optimization features that reduce the need for manual defragmenting:


The TRIM command deletes unused blocks on SSDs so they can be reused. This prevents the performance degradation that occurs when SSDs have too many scrambled free blocks.

Garbage Collection (Mac OS)

Mac OS runs an automatic garbage collection on SSDs to clean up unused blocks, maintain performance and reduce fragmentation.

Automatic defragmentation

Windows and Mac OS now have automatic defragmentation schedulers that run in the background when the system is idle. This transparently consolidates files without user involvement.

OS Auto defrag technology
Windows Disk Defragmenter
MacOS Hot file adaptive clustering

Do you still need to defrag in certain cases?

For most general desktop and laptop usage, defragmenting is no longer necessary. However, there are some cases where it might still be recommended:

  • Older mechanical hard drives – defragging will offer performance improvements
  • Almost full hard drives – less free space increases fragmentation
  • Frequent writing/deleting of large files – can lead to fragmentation
  • Systems used for audio/video editing – need optimized data access

You can analyze your drive’s fragmentation with built-in tools like Disk Defragmenter on Windows or Drive Genius on Mac. This will tell you if you could benefit from defragging. Always remember to backup first!

Should you buy a dedicated defrag software?

There are third party defrag tools advertizing enhanced algorithms and deeper optimization. Some popular commercial options include:

  • Diskeeper
  • O&O Defrag
  • Perfect Disk
  • IObit Smart Defrag

However, for most users the built-in auto-defrag tools are good enough. Third party software generally won’t provide significant gains for typical computer usage. You’ll mainly see benefits on frequently used media editing workstations dealing with large files.

Key points:

  • Don’t needlessly defrag SSDs as it decreases lifespan and offers no performance benefit.
  • Ensure TRIM is enabled on SSDs to maintain optimal performance.
  • Only defrag HDDs if you are experiencing noticeable slowing and fragmentation issues.
  • Backups are crucial before defragging in case anything goes wrong.
  • For most users, built-in auto-defrag is sufficient.


Defragmenting is now largely a relic from the past. Modern file systems, improved hardware and built-in optimization in operating systems have removed the need for regular manual defragging. For typical desktop and laptop PCs, it can usually be left in the hands of automatic tools. Only consider third party defrag software for specialized situations dealing with heavily fragmented drives. Otherwise save your time and money and leave defragging to the dustbin of unnecessary computer maintenance tasks.