Read this article in SpanishIntroduction
When testing defragmenter software, we evaluate it with these parameters:
- Speed of analysis on fragmented files: Isn't it speed we want from our computer?
- Speed of defrag;
- Some extras: such as scheduled defrag, shutdown PC when done, etc.;
- Defrag capabilities: Why is this placed in last position? Because almost all of today’s defragmenters can perform this task with very similar results.
With these parameters in mind, we found a few we could recommend with the best of these as good as any commercial product.
Read also Fragmentation: Why does it happen? and Defragmentation: Do you need it? at the end of this page.
Rated Products

Platforms/Download: Windows (Desktop) |
Version reviewed: n/a
Gizmos Freeware
| Our Rating: 5/5 |
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Platforms/Download: Windows (Desktop) |
Version reviewed: n/a
Gizmos Freeware
| Our Rating: 4.5/5 |
Read more...
Platforms/Download: Windows (Desktop) |
Version reviewed: n/a
Gizmos Freeware
| Our Rating: 4/5 |
Read more...
Platforms/Download: Windows (Desktop) |
Version reviewed: n/a
Gizmos Freeware
| Our Rating: 4/5 |
Read more...
Also reviewed but not included:
- Puran Defragmenter
- O&O defrag free edition
- Others
Feel free to suggest any software not already mentioned for review.
Related Products and Links
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- Types of Backup Software : What’s the difference between Disk Imaging, File Based Backup, or Synchronization, and which should I use?
- Best Free Drive Cloning Software
- Best Free Folder Synchronization Utility
Fragmentation: Why does it happen?
Suppose you are browsing the web, downloading your favorite songs and installing an application all at the same time, how does your system write all these files without any interruption to your activity? Well it's simple: it responds to all applications' write requests (I/O operations) by writing all files at a continuous location on your disk.
Representation of a disk track:
(Fig. 1)
Yellow: Temporary written internet files
Red: Installation (Game)
Blue: Song cache
The purpose of disk defragmenters is to reorganize such files which are supposed to be together. An ideal situation after defragmentation would look like this:
(Fig. 2)
But what happens when you uninstall, delete, or simply clean your temporary files? Imagine yourself uninstalling the application (game) you installed. The disk could look like this:
(Fig. 3)
The white zone is empty space without fragmentation. A disk looking like this will have just a little or even imperceptible impact on performance. In this case defragmentation is needed but not critical.
The last thing you want to see is a hybrid combination. Files very fragmented fig 1 and empty disk space fig3 but instead of contiguous clean sectors you'll find what we call fragmented empty space. And this is what it looks like:
(Fig. 4)
This is the worst case scenario. Overall system performance will be compromised and fragmentation is critical. You should defragment (defrag) or let your defragmenter schedule and execute the defrag process for you.
Defragmentation: Do you need it?
Standard mechanical HDDs (hard disk drives) will benefit from defragmentation and continuous disk use, because when spinning, it keeps remagnetizing the HDD plates. But if you own an SSD (solid state drive) you SHOULD NOT defrag or install any defragmenter application because it will shorten the life of the drive.
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Comments
With mitch permission, I'll recommend you to make a disk check:
-Command prompt
chkdsk /f /r /b (could take a while)
I suspect a corrupted mft
Are you recommending that I schedule Check Disk?
If so, I just ran it after I uninstalled Auslogics and installed Defraggler.
What is a corrupted mft?
What is mitch permission?
I'm sorry, but I simply don't understand the jargon.
It is not logical that, eventhough Auslogics' optimize and defrag times have increased, that Defraggler takes greater than a day to defrag.
If that's normal, than I'll look elsewhere.
Sorry about poor explanation
A corrupted Master File Table could lead to slow information retrieve from disk so is slows down average read. Defrag use MFT to organize files.
You have two different defragmenters with different algorithm, so is normal it display different estimated time.
Yes. I recommend you to open an elevated command prompt and run a check disk
If you need more help how to do this, please ask.
rmitch is the former editor of this section, and I'm the older editor so, with his permission I'll take your question
Thanks for the help...
Chkdsk ran all night, didn't find anything.
Everything is OK, which I knew it would be.
I had just run chkdsk a week or so ago when I uninstalled Auslogics - there was nothing then, nothing now.
Not sure where to next...I am still baffled why Defraggler was taking so long in either mode, quick or full on defrag.
Thanks Anup.
D@mn, guy, you still as fast as a thunder
OK - will let you know what I find.
Thanks.
"my defrag" totally screwed up my hard drive. I dl'd it and ran it one time. It made ALL my movies unusable, and to make matters worse I went from 8% fragmentation to 32% at completion! It took days to straighten out, and if I wanted to fragment my sys I couldn't of done a better job of screwing it up than this one did!
I'm sorry but Disktune will no longer be available. A second release was planned but Joep (the man behind Disktune) in that time told me "So, yes, I do have plans for the tool, just need to find the time" but that was in October 2012. It's sads news for everyone. Anyway, thanks Joep end thanks Disktune for such great piece of software.
I think DiskTune may now be discontinued. It doesn't seem to be listed on their site and the link to it above doesn't work btw.
Sorry if repost.
My external hdd (seagate) has bad sectors. Do these defragmentation tools skip the bad sectors? Do they even detect them?
About MyDefrag; Just a "heads up": mydefrag.com appears to be down today. I don't know if that means it is dead or just offline but...
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