Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

The built-in defragment tool of Windows is not the best one. I heard that there are a ton of better ones out there - but which one is really good?


locked by voretaq7 May 29 '13 at 17:02

This question exists because it has historical significance, but it is not considered a good, on-topic question for this site, so please do not use it as evidence that you can ask similar questions here. This question and its answers are frozen and cannot be changed. More info: help center.

closed as not constructive by kce, RolandoMySQLDBA, voretaq7 May 29 '13 at 17:02

As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance.If this question can be reworded to fit the rules in the help center, please edit the question.

21 Answers 21

up vote 11 down vote accepted

I use Jkdefrag and read good things about it. Can be used as screensaver as well, have a 64-bit version and is open source.

Edit : As of version 4, it's now called MyDefrag.

+1. I have the commercial Diskeeper but I prefer the Free JkDefrag. I do not have a comparative stats on the two software but I can really tell the difference from the performance of my laptop. ;-) – MarlonRibunal Apr 30 '09 at 22:03

For a free option at small shops I've been a fan of Defraggler

I also love defraggler! – Drewdin Apr 2 '12 at 17:50

The necessity of a good 3rd-party defrag tool isn't quite what it used to be, though they're of course still hotly peddled as cure-alls beside generic system cleaners.

The NTFS file system is quite an improvement over FAT32 in this regard, and this TechNet blog article discusses some of Vista's improvements in particular: Don’t judge a book by its cover – why Windows Vista Defrag is cool (nonpartisan I know ;).

For Vista:

I'm putting forward that a 3rd party defrag tool is entirely unnecessary. The system scheduled idle defrag (find it in Task Scheduler->Microsoft->Windows->Defrag) is more than capable of keeping up with system fragmentation and a manual defrag has little benefit of significance. (Although by all means if you wish to target highly specific performance sensitive problem files and directories with the likes of contig as mentioned you should do so.)

I believe this is verifiable by simply running the utilities in question and noting that the reported fragmentation is within practical performance levels. (See the article for possible misconceptions.)

Back to the original question: If you merely want to replace this scheduled task with a good defrag tool then my recommendation is for the Windows one already in use, at least on Vista. ;)

On earlier versions of Windows I'd vote for Perfect Disk merely on the result of my past "x vs x", "x better than *", and "x compared to *" Google queries (try the wildcards). For anyone really gung-ho about a substitute for Vista's I'd probably suggest it there as well, or at least the Google searches for comparative research.


Perfect Disk

I use the Windows Home Server Edition which gives you 10 licenses for all your home computers.

The normal Home Edition is inexpensive at $30.


Diskeeper is one of the ones that usually gets mentioned. The Microsoft defrag utility is a limited version (severly) of the Diskeeper disk defragmenter, as per KB130539.


defraggler has always suited me fine, I've no idea if its any good. But it's portable and appears to work.

share – Ben Alpert Apr 30 '09 at 21:47

JkDefrag, it's open source, fully automatic, can be run as a screen saver or from a Scheduled Task.

JkDefrag is a disk defragmenter and optimizer for Windows 2000/2003/XP/Vista/2008/X64. Completely automatic and very easy to use, fast, low overhead, with several optimization strategies, and can handle floppies, USB disks, memory sticks, and anything else that looks like a disk to Windows. Included are a Windows version, a commandline version (for scheduling by the task scheduler or for use from administrator scripts), a screensaver version, a DLL library (for use from programming languages), versions for Windows X64, and the complete sources.


Defraggle is good stuff

You linked to Defraggler, which was already mentioned. – Jim McKeeth Apr 30 '09 at 22:01

Sysinternals (now bought by Microsoft) made a free command line tool called Contig that at least have one nice feature in that you can point it to a directory and it will defrag only that and the subdirectories but not the rest of the disk. I have no experience with the other programs mentioned in the other answers. The performance hit when running contig is noticeable.


My site just deployed 'PerfectDisk'. It looks to be a good tool and can be centrally managed and deployed to the Desktops. I just ran a few defrags with it and it did improve speed and has a detailed interface letting you know what's going on.



IOBit SmartDefrag is fantastic -- we used to shell out for the cadillac version of Diskeeper for our servers, but now we just use SmartDefrag. It's got all the functionality in the sfotware we were paying for, and even has a feature that optimizes the placement of more frequently used files.


Disk Keeper is the best defrag util that you can pay for according to many reviews...


i've tried Diskeeper, O&O Defrag and the rest. i find PerfectDisk to be the best.

It actually defragments my hard drive, rather than complaining when there isn't 20% free space. It also doesn't try to be an enterprise defragmenter, or a defragment-while-you-work product - taking up computer resources and causing I/O delays while i'm working or playing.

i schedule it to run at 1:00 AM. It runs at 1:00 AM, and then stops running.

Based on your recommendation I just tried PerfectDisk and am very impressed. I'll be switching over to it immediately on all my machines. – Scott May 29 '09 at 3:51

I recommend the open source UltraDefrag. It has boot time defragmentation, a feature implemented by the author at my request.


O&O Defrag


I use Magical Defrag, It is pay software at about $20 depending on where u come from but it does a good thorough job.


I like defraggler from Piriform.


I recommened iobit's Smart Defrag


I've found it does a better job than the built-in defragger (Diskeeper Lite in disguise), but so far the best defragger I've used has been O&O Defrag Professional. (I do not work for them.)


I've used IOBit Smart Defrag without any problems. As you mentioned, I like how it defrags in the background. (I too do not work for them)


I'd second PerfectDisk as my defragger of choice. Newer versions also have "enterprise defrag" options like particular defrag strategies for specific environments (eg: VMWare virtual machines & SQL)


Not the answer you're looking for? Browse other questions tagged or ask your own question.