Gizmos Needs You

Gizmo's Freeware is Recruiting

 We are looking for people with skills or interest in the following areas:
 -  Mobile Platform App Reviews for Android and iOS
 -  Windows, Mac and Linux software reviews       Interested? Click here



Best Free Disk De-fragmenter

Other Language?
  Read this article in Spanish
In a Hurry?
  Go straight to the Quick Selection Guide

Fragmentation: why it happens

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.

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.

So when testing defragmenter software we are going to evaluate it with some 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.

Well, it's time for action now and let me introduce you to the de-fragmenters.


UltraDefragUltraDefrag is simple yet has a lot of customizable options through text files and scripts via two mouse-clicks. Not only is the defragmentation super fast, but also you are not going to notice it's working! You can keep doing your things while UltraDefrag does what was born to do… defrag. It performs so well you are going to want to carry it in your wallet. A lot of varied boot defrag commands. If your goal is to optimize your system startup at maximum, this is what you need.


MyDefragMyDefrag, JK defrag with a GUI (Graphical User Interface). Bad? No, just awesome!

Unbelievable power user options for everyone without having to configure any script. Just select the option that best suits your needs and it's done. MyDefrag employs an algorithm that places the most used files at the beginning of the disk. This decreases access times because the actuator arm of the hard drive has no need to move to the end of a disk to search a file.

If you don't know what a HDD looks like, please see below:

The trick revealed and a little science.

When you turn off your computer (or Windows shut downs your HDD), the actuator arm has a designated "landing zone" (a specific sector at the beginning of the disk) that remains stationary until the next startup. This is to avoid disk scratch and therefore, data loss (data is read via magnetism, touching surfaces is not required). When turned back on, the closest sector to the actuator arm is already near the "landing zone" (beginning of the disk) so it's faster to read files on that sector than others in outer zones of the disk.

Also, the surface distance travelled is considerably less in the inner sectors of the disk. So, placing files at the beginning of the disk is the best idea.

MyDefrag is not the only defragmenter capable of doing this, as many others include an option. However, MyDefrag achieves this in a much simpler way. This is combined with a good “fast defrag”; the choice of specific options, many others by scripting, and excellent defragmentation methods and simple scheduler options.


This little boy, DiskTune, is not exactly a kid. Despite the use of Windows API to do defragmentation jobs, it's incredibly fast, simple and lightweight. Many useful options just a couple pixels of distance. Direct access to usual options such as Analyze, Defrag (quick), Optimize (rearrange) and Compact (defrag free space). The best thing about DiskTune? The ability to create a shortcut to your desktop and then double-clicking it to run a fully customized defrag. Four words—“one size fits all”.


Defraggler thumbnailPiriform's Defraggler—The first thing that caught my attention when first opening Defraggler was a green word, GOOD. I quickly realized it was telling me about S.M.A.R.T. Status (information provided by the disk itself, reporting temperature etc). This is a great feature and has its own tab on the program for detailed view.

In terms of defragmentation ability, Defraggler is one of the best choices you could make. It performs a very fast “quick defragmentation” with decent file reorganization but if you perform a complete defrag process, which takes longer, you obtain results that are worthwhile. Your files will be together as they should be as solid as a concrete wall. Defraggler also supports scheduling, low priority and boot defrag. Highly recommended.


MyDefragmenterMyDefragmenter, Ultradefrag with a very simple, intuitive GUI plus a full scheduler which has the ability to program defrag while shutting down or starting up computer. Includes a 24/7 support by phone call and online help.


Auslogics Disk Defrag thumbnailAuslogics Disk Defrag is another quality disk defragmentation program. During a fresh installation the installer asked if I wanted to install a Tool Bar and/or change my home page. These were easily de-selected before the installation process began. Auslogics Disk Defrag can be ran from a easy to understand GUI (Graphical User Interface) or you can use the command line tool for more advanced users. Auslogics also optimizes defragmented files and space by defragmenting free space and moving system files to the fastest part of the disk. The software is designed to defrag multi-terabyte volumes. If you choose you can defragment a particular folder or a single file by selecting the file out of a list of fragmented files. The program is set-up for automated defragmentation and will allow you to analyze your disks before you defragment. Auslogics also has a portable version available which can be run directly from your USB drive. Both versions are free and are allow for home or commercial use. The developers also have several articles regarding defragmenting your hard drive including How to defrag your drives the right way: 7 defrag tricks to learn today". This article includes topics such as temporary files and how to prevent the loss of your system restore points. The software only supports 64 bit on Windows 7/8 operating systems. The developers have updated this software twenty-four times in the last thirty four months, eleven of those were in 2012. Needless to say continued development of the product remains strong.  I have used this program on all of my computers for the last couple of years without any issues. Operating systems I have successfully operated on include XP 32bit; Windows 7 32 & 64bit.


Also reviewed but not included:

-Puran Defragmenter

-O&O defrag free edition



Feel free to suggest any software not already mentioned for review.

Quick Selection Guide

Gizmo's Freeware award as the best product in its class!

Runs as a stand-alone program on a user's computer
System files defragmentation. Incredibly fast in all tasks. Power (scripting) features.
Some settings only accessible by configuration file (txt).
681.6 KB
32 and 64 bit versions available
Open source freeware
A portable version of this product is available from the developer.
This version will install on PCs running: Windows XP / 2003 / Vista / Windows7 / XP64 / Vista64 / Windows7 64
Runs as a stand-alone program on a user's computer
For average and power users
Not regularly updated
2.035 MB
32 and 64 bit versions available
Unrestricted freeware
There is no portable version of this product available.
Windows 2000, 2003, XP, Vista, 2008, Win7, and for X64.
Runs as a stand-alone program on a user's computer
Very Fast. Can create shortcut to double click customized defrag.
Windows API. Needs to improve system resources usage
1.06 MB
32 and 64 bit versions available
Unrestricted freeware
There is no portable version of this product available.
This version will install on PCs running: Windows XP / 2003 / Vista / Windows7 / XP64 / Vista64 / Windows7 64
Runs as a stand-alone program on a user's computer
Very solid piece of software. Updated regularly. Now with S.M.A.R.T. monitoring.
No optimization feature yet.
3.6 MB
32 and 64 bit versions available
Unrestricted freeware
A portable version of this product is available from the developer.
This version will install on PCs running: Windows XP / 2003 / Vista / 7 / 8 /
Runs as a stand-alone program on a user's computer
Well recognized Ultradefrag engine. Excellent scheduler.
Not regularly updated.
1.8 MB
32 bit but 64 bit compatible
Feature limited freeware
There is no portable version of this product available.
Windows 7, Vista, Windows XP

Running on x64 computer requires download and replace DLLs available at Mydefragmenter website

Auslogics Disk Defrag
Runs as a stand-alone program on a user's computer
Very fast at analyzing and performing a quick defragmentation.
Optimize function could be faster.
5 MB
32 bit but 64 bit compatible
Unrestricted freeware
A portable version of this product is available from the developer.
Win 8 (32 or 64 bit), Win 7 (32 or 64 bit), Vista SP2 (32-bit only), XP SP3 (32-bit only)


This software review is copy-edited by Ian Richards. Please help edit and improve this article by clicking here.

defrag disk, defragment hard disk, disk defragmenter, free disk defrag software.

Back to the top of the article


Share this
Average: 4.1 (204 votes)
Your rating: None


by 4goTTen21 on 31. December 2011 - 21:03  (86291)

New editor. new reviews . Try the new products and write down your opinion!

by shalin on 14. March 2012 - 9:50  (90557)

If you are going to dump off a previous no 1, then you might need to explain it why you are doing so. "I'm the new editor so I dumped it" is not good enough.

by snickers and mars (not verified) on 14. December 2011 - 23:50  (85031)

i want a software that doesnt optimize and doesnt comperes like smart defrag

only it do is defrag

by 4goTTen21 on 15. December 2011 - 0:19  (85032)

Manually guided or automated?

You can download and try My defrag it comes with a wizard, just select defrag, next and you're done .

by snickers and mars (not verified) on 15. December 2011 - 0:46  (85034)

does it not have compress feature like smart defrag

in smart defrag you cant turn it off

by snickers and mars (not verified) on 15. December 2011 - 0:48  (85035)

i read this about it

MyDefrag employs an algorithm that places the most used files at the beginning of the disk

i dont want this

by 4goTTen21 on 15. December 2011 - 1:18  (85037)

So you know about defrag algorithms. Read the full review, make a choice based on it. If you have advanced skills as algorithm analysis, surely you can make the right choice through all reviewed products.

by Sputnik (not verified) on 10. December 2011 - 22:37  (84777)

I use two different defragmenters : MyDefrag and Puran Defrag.

I use MyDefrag for a big mensual defragmentation and Puran Defrag for the automatic defragmentation.

I have made a comparison of both Puran Defrag and IObit SmartDefrag which are the only freewares to do automatic defragmentation, I think, and Puran Defrag is really the best.

You may verify by yourself if you wish : download and install each one and leave each one to work a couple of hours and afterwhile do an analysis only with MyDefrag which will indicate what your driver really looks like.

Take a screenshot of MyDefrag and keep it. Run the other defragmenter a couple of hours and do the same.

Compare the two snapshots and you will clearly see that Puran Defrag does a better job than IObit SmartDefrag.

by George.J on 9. December 2011 - 15:10  (84713)

Am I missing some OS concepts, which I have studied long back.!! What does the optimize function do in addition to normal defragmentation? Doesn't normal defragmentation store files into contigous regions and does the compaction process?

By the way, Puran Disk Defrag Free has a clean GUI which I liked and does its job well as well as have an Intelligent Optimizer. I would like to find it's review here sometime :-) Sadly there's no portable version.

by 4goTTen21 on 9. December 2011 - 16:49  (84721)

Hi George. There are many defragmenters with different types and concept of defragmentation (normal, quick, "just defrag", optimize, consolidate, etc). Generally, "basic" defragmentation is just put together the "sparse" pieces of the same file, while "optimization" may refer to many different actions (sorting files in disk by usage, sequence by size and many, many more). You also could hear about consolidation, and it may bereferring to empty space. Used language could be confusing because terms differs from one software to another; so to answer your question let's take Windows built-in defragmenter as example:

-Defrag: link scattered files in one file (when possible)
-Optimize: rearrange most used files in order to gain high response to I/O requests
-Consolidate: (defrag free space) separate already defraged files (separate as a unit whenever it's possible) from free space so new writes on disk has no need to be performed among other files (no need to jump to empty space because it's contiguos blank space).

Please, remember defragmeners may refer with different words to the same action or conversely.

by George.J on 9. December 2011 - 17:26  (84722)

Thanks for an informative and helpful reply. Certainly Optimize takes longer time and in most cases Defragmentation will suffice for better performance. I guess it's better to use the optimize function just once a month or so.

by Johnny 5 on 7. December 2011 - 23:03  (84603)

I have a question that I haven't seen asked here. At least not to my knowledge but has anyone other than me have found that using some of these third party defraggers have completely erased all of their system restore points? Puran, MyDefrag and I think Auslogics completely erased all of my System Restore points. I have now gone back to using the Windows 7 defrag and have not lost a single Restore Point. I'm using Windows 7 64 Home Premium. Thanks

by 4goTTen21 on 7. December 2011 - 23:53  (84610)

It's a strange situation you pose here. Something like this never happened to me with none of the reviewed defragmenters and generally, no other software.

by Johnny 5 on 8. December 2011 - 0:31  (84613)

I emailed Puran a while back because of it and here is their reply if it helps. FYI, I'm not the sharpest knife in the drawer when it comes to computers.

Thank you for your email.

This is actually a limitation of Windows shadow copy service as it considers any data movement by defrag API as updation of the files and hence sometimes restore points are deleted.

To overcome this, Puran Defrag suggests under its VSS Compatibility section of its help file the following -

· It is highly recommended that you format your drive with cluster size of 16K if you want to defrag it and also do not want to loose Shadow Copies.

· If above is not possible for you then to configure Puran Defrag so that data movement is minimum and shadow copies are not lost or the loss is minimum, uncheck Additional Operations including Fill Gaps, Optimize Drectories, Free Space and PIOZR.

by 4goTTen21 on 8. December 2011 - 0:53  (84615)

Thanks to mention VSS. This is happening not by a limitation of VSS, but a parameter that set max space available to VSS copies. Setting a lower than 16 KB cluster may lead in faster fill of volume (please try not to change defult cluster size). However, VSS service only delete older copies first. If your defragmenter has built-in VSS compatibilty mode, please activate it.

by sampler on 6. December 2011 - 13:40  (84503)

Please review O&O Defrag and Puran Defrag.

by 4goTTen21 on 6. December 2011 - 17:04  (84517)

I'll have it on mind. Keep an eye on review.

by A_Nonny_Mush (not verified) on 1. December 2011 - 0:55  (84204)

Thanks for bringing Disk Tune to my attention. I have an old lappy with XP on it (Although I mainly use Linux) and it seems to be a very good defragger. Yes it aint pretty but there's plenty of pretty looking 'Defragmenters' that are about as useful as a chocolate fireguard. Kudos to the new reviewer, it's now a much better article anyway:)

by 4goTTen21 on 1. December 2011 - 0:59  (84205)

Thanks G.

by toastane (not verified) on 30. November 2011 - 22:25  (84192)

I ran in to problem where some app would create lost clusters a lot. on a computer that ran constantly then the drives would go to protected mode and run slow as snails.

I read that some Defragmenters will detect lost clusters and repair them but cannot find a list anywhere of which will and can run in the background monitoring things.
Any ideas?

by 4goTTen21 on 30. November 2011 - 23:09  (84197)

Yes. Please don't try to repair cluster with no other tools than those built-in Windows.
Properties (Over HDD)> Tools > Error Checking (at this point, depending your OS, you could see 2 options; usually the 2nd is the best working, it performs the deepest scan and repair).
If you are planning to use non Windows tools, please take a look:

by Joe Simons (not verified) on 28. November 2011 - 21:07  (84068)

I tried 'DiskTune'...

OMG, it took AGES!!! to Optimize just a 80GB HD on my old 2.6GHz/4GB RAM PC which runs Windows 7 Home Premium.

No way, Mister!

by 4goTTen21 on 28. November 2011 - 22:39  (84076)

Try disabling background process.
I made this review, based on the results obtained from "frozen" systems so the accuracy of comparative is 99%. Also I've tested all of this products in a low and a high end PCs. The low end:

-80GB Caviar Green HDD ATA/EIDE 166 MB/s 7200 rpm
-Only 768 MB of RAM
-PENTIUM D315 2.26 GHz

As you see, that configuration is lower than the one you mention. And DiskTune runs faster enough to be the fastest of all defragmenters tested. But was not choosen as the G.F.B.P.I.C. because te average user could feel intimidated with its interface. Thank you.

P.S.: I should add, running Windows Vista, 7 and 8 is enough problem for this old pc. Imagine when running DiskTune ( used all available CPU resources , that mean faster)

by Joe Simons (not verified) on 30. November 2011 - 10:52  (84168)

1) Which BackGround process are you referring to?

2) What does 'G.F.B.P.I.C.' means?


by 4goTTen21 on 30. November 2011 - 18:27  (84183)

Sorry for not being explicit. G.F.B.P.I.C. means Gizmo's Freeware Best Product In Category.
Background process like those which eats your processor. An example, if you are using Microsoft Security Essentials as your default protection, it could be checking whatever the defragmenter is doing. Antivirus programs is just an example. Check on task manager what could be interfering with defrag process. If you feel experienced doing this, you can disable with your criteria the process that mess with your defragmenter.

by Joe Simons (not verified) on 27. November 2011 - 17:43  (84000)


1) Why the Auslogics Disk Defrag is No Longer included in the List?

2) A few months ago, the Auslogics Disk Defrag was on the top of the list. Now, it isn't even mentioned...
Is there something wrong with this program we need to know about?

Thank you in advance!

Keep up with the good work!!!

by 4goTTen21 on 27. November 2011 - 17:53  (84001)

Hi Joe. Auslogic was removed from review just some days ago. There's nothing wrong with the functionality of the product. An update of the review took place at the same time new product was included on the review. Hope you test it and tell us if you like it. Greetings.

by Joe Simons (not verified) on 28. November 2011 - 8:58  (84041)

I gave Auslogics a try today:

It asked me to install the 'Auslogics Toolbar' and make '' my Home Page.
I unchecked the respective Checkboxes!

It is very Fast, but this means Nothing to me:
I care more for the De-fragmentation Effect/Result
than for the Time required for it.

Defraggler and MyDefrag offer, by far, better Results.
I don't know if this happens only to my system...

I wish I could see a De-fragmentation Comparative though...

I will add to those Posters who want to see a
Puran Defrag Review, here.


Keep up with the Good Work, here!!!

by Radelen (not verified) on 30. November 2011 - 21:17  (84189)

"It is very Fast, but this means Nothing to me:
I care more for the De-fragmentation Effect/Result
than for the Time required for it.

Defraggler and MyDefrag offer, by far, better Results.
I don't know if this happens only to my system..."



by Anonymous123 (not verified) on 26. November 2011 - 17:14  (83942)

I hope Puran is reviewed at some point. Not mentioning Puran in the review brings some credibility problems. The reviewer's recommended defrags may all be better than Puran in the reviewers opinion but Puran needs mentioned as it is generally considered a top defrag program across the internet. Secondly, not mentioning the advances in the Vista and Windows 7 built in defragger is problematic because it appears the reviewer is simply ignoring the built in defragger. That may very well be the case, but if this review is about alternatives to the Windows defragger the review should state that.