• Navigation
  • open search





Download Editors' Rating:
Editors' Rating:
Average User Rating:
out of 3021 votes out of 0 votes

Quick Specs

  • Version:
  • Total Downloads:
  • Date Added:
    Apr. 19, 2017
  • Price:
  • File Size:
  • Downloads Last Week:
  • Platform:
  • Product ranking:

Editors' Review


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).


Smarter: A new and smarter defrag engine recovers more free space on traditional hard disks but skips solid-state drives (SSDs), which should never be defragmented. The Smart Optimize tool analyzes your system and combines Defrag, Optimize, and Prioritize processes based on speed.

SSD Trim: Smart Defrag 4's Trim tool applies the important TRIM command that helps keep your SSD clean and fast. The Trim tool even has its own disk map.

Accessible disk map: Smart Defrag 4's Settings thoughtfully include an accessible disk map optimized for color-challenged viewers.

Boot Time Defrag: Smart Defrag 4 can quickly defrag drives at boot, and you can easily skip the process and get right to work if you need to. No worries; Boot Time Defrag won't defrag your SSD boot drive.


SSD DIY: Real power users may still prefer their own SSD tweaks to Smart Defrag 4's Trim tool.

Bottom Line

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

read more +
read more +


User Reviews
  • Current Version

    0 stars Be the first to review this product
  • All Versions


    out of 3021 votes

    • 5 star 1522
    • 4 star 1107
    • 3 star 159
    • 2 star 76
    • 1 star 157
  • My rating

    0 stars

    Write review

Update Your Review

Since you've already submitted a review for this product, this submission will be added as an update to your original review.

The posting of advertisements, profanity, or personal attacks is prohibited.
Click here to review our site terms of use.

see all reviews +

Full Specifications

What's new in version
  • Optimized user interaction for more user-friendly experience.
  • Supported optimizing more NCsoft games in Game Optimize for better gaming experience.
  • Improved engine for more efficient defrag.
  • Updated multiple languages.
  • Fixed known bugs.
Publisher IObit
Publisher web site
Release Date April 19, 2017
Date Added April 19, 2017
Category Utilities & Operating Systems
Subcategory System Utilities
Operating Systems
Operating Systems Windows XP/Vista/7/8/10
Additional Requirements None
Download Information
File Size 10.39MB
File Name smart-defrag-setup.exe
Total Downloads 23,510,718
Downloads Last Week 21,669
License Model Free
Limitations Not available
Price Free

Previous Versions:

Add to my list Report a problem
read more +