Higher File Access Speed
Disk fragmentation is generally the main cause of slow and unstable computer performance. In order to accelerate hard drive for faster data access and outstanding disk performance, Smart Defrag 4 provides efficient defragmentation to hard drives and SSD by optimizing file placement and consolidating free space. Then you can enjoy higher game launching speed, and copy files with only half of the time as before, etc.
Up to 100% Faster PC Startup
Specific boot files in the system disk are not allowed to be moved safely while Windows is running, which causes a slower and slower system startup. The Boot-time Defrag feature of Smart Defrag 4 will easily do this job for you before the operating system is fully loaded. In this way, you can enjoy faster PC startup and top running speed with the most stability.
Safe & Automatic Disk Defrag
Smart Defrag 4 not only provides disk defragmentation as any other tool does, but also optimizes it by intelligently streamlining your files based on using frequency. With IObit latest disk defrag engine, it is just as safe for your files as using Windows. And you just need to install & forget it. Smart Defrag 4 will automatically work for you with no data lost.

Media Review

"IObit Smart Defrag 4 is the best defragger we've tried yet."

"IObit Smart Defrag 4 optimizes your PC to take full advantage of SSD performance while defragmenting your hard disks. Its SSD Trim tool automatically enables system tweaks that typically require experience to apply. Smart Defrag 4's updates include a new defrag engine, specialized Game Defrag, a cool new look, and many more language options (35 and counting)."-Cnet

User Review

"Smart defrag is a very well behaved disk defrag software."

"Smart defrag is a very well behaved disk defrag software, operating in the background whenever computer is idle so that you hardly notice it. As a result: drives are permanently defragmented allowing rapid access and less wear and tear. Smart defrag is the best Free disk defragmenter I've ever used and I'll definitely recommend it to my family and friends!"

"It is easy to use, must have utility, for your hard disc or SSD."

"I run a combination of RAID 0 SSDs and RAID 0 HDDs and use Smart Defrag Pro to analyse, defrag and keep my drives running at peak performance. As with all IObit software it is easy to install, use and very reliable. Just set it up and forget it. Smart Defrag has a very small memory foot print so it won't slow down your system. Definitely recommended!"

"Since using this fantastic software my desktop and my laptop are fast and save."

"I am a user of Smart defrag for many years. Since using this fantastic software my desktop and my laptop are fast and save. Together with advance system care ultimate you have a complete tool for keeping you system up to date, fast and secure.Using it every day without need to wait (pc closes itself) you keep your system in top condition even if you have no technical background!"
  • Amnon
  • Edward Lee Ah Yen
  • Hans

Over 7,000,000 User's Choice

Maximum Hard Drive Performance & Higher Data Access Speed

Free Download

V 4.3.0 | 7.57 MB
Supports Windows XP/Vista/7/8/8.1/10
"IObit Smart Defrag 4 is the best defragger we've tried yet."
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