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iDefrag for Mac

Disk defragmentation and optimization tool.

Free
In English
3.8
Based on 123 user rates

iDefrag overview

iDefrag helps defragment and optimize your disk for improved performance.

iDefrag Features
  • Supports HFS and HFS+ (Mac OS Extended).
  • Supports case sensitive and journaled filesystems.
  • Supports adaptive hot file clustering ("Hot Zone").
  • Four powerful defragmentation algorithms:
    • Compact data, moving all free space to one place.
    • Optimize filesystem metadata.
    • On-line defragmentation.
    • Defragment whilst your disk is mounted.
    • Advanced programmable optimization.
    • Rearrange your disk the way you want.
  • B-Tree metadata file compaction/optimization support.
  • High-performance user-defined file classification engine.
  • Per-block and accurate whole disk display.
  • Detailed statistics so you know whether you need to optimize.
  • Inspector allows you to view details of individual extents/files.
  • Quickly jump to specific files to examine them in more detail.
  • Altivec accelerated display for improved performance.
  • Auto-update feature ensures you always have the latest version.
  • Fine-grained security, just like iPartition.
  • AppleScript support.

Note: Coriolis Systems Limited is shut down and does not provide any support for its products. The license information can be obtained from the Coriolis Systems' website

What’s new in version 5.3.1

Version 5.3.1:

Note: This product is not compatible with macOS Mojave and later.

A free license from the developer is available here

iDefrag for macOS 10.10-10.11
iDefrag for OS X 10.6-10.9
iDefrag for OS X 10.4-10.5
iDefrag for OS X 10.3

View older iDefrag versions

iDefrag for Mac

Free
In English
Version 5.3.1
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3.8

(289 Reviews of iDefrag)

  • Comments

  • User Ratings

deanolatte
deanolatte
Feb 13 2023
5.3.1
0.0
Feb 13 2023
0.0
Version: 5.3.1
I used this to defrag ever since it came out. However, I stopped using it since os x Lion. I now find I need it, so, I downloaded it with the license key yesterday. However, the company is off line and cannot confirm my purchase. I must have the original CD somewhere but I haven't used that in years. Is there a way to get through the problem to get it working again?
Aargl
Aargl
Jan 2 2022
5.3.1
0.0
Jan 2 2022
0.0
Version: 5.3.1
You can read nearly everywhere that defragmenting is now useless and probably was never neededin MacOS: well, there's at least a few areas where it's really helpful, such as sparsebundles, if you use them. Not only it allows you to reclaim free unused space (and sometimes a lot!) but the disk is mounting faster and all operations that use it benefit from defragmentation. I've got mail archives from 20 years of Microsoft Outlook identities stored that way and the difference was plain to see! Thanks a lot Coriolis.
philstar22
philstar22
Jan 21 2021
5.3.1
0.0
Jan 21 2021
0.0
Version: 5.3.1
Well, neither my main hard drive, no the external hard drive I actually downloaded iDefrag to defrag actually showed up in the program, so it was completely useless to me. The only thing that showed up, in fact, was the disk image installation thing of idefrag. Strange.
dominym363
dominym363
Oct 28 2020
5.3.1
0.0
Oct 28 2020
0.0
Version: 5.3.1
Can someone explain what the license to use this program is. What is a license file?
lgm1146
lgm1146
Jul 7 2020
5.3.1
3.0
Jul 7 2020
3.0
Version: 5.3.1
iDefrag required to restart my mac to be able to work with the hdd (which is only one in my mac, where is also OS installed) and now it got stuck for more than 10+ hours in the loading screen (apple logo - at startup)... should I abort it by turning off the mac? Anyone knows it's frozen or what should i do? Thanks a lot guys
lgm1146
lgm1146
Jul 7 2020
3.0
Jul 7 2020
3.0
Version: null
apk412
apk412
Jul 11 2019
3.0
Jul 11 2019
3.0
Version: null
neartheredrocks
neartheredrocks
Jul 9 2019
5.0
Jul 9 2019
5.0
Version: null
Fariborz
Fariborz
Jul 9 2019
5.0
Jul 9 2019
5.0
Version: null
djrobmoore
djrobmoore
May 11 2019
0.5
May 11 2019
0.5
Version: null
Jim-Guy
Jim-Guy
Apr 29 2018
4.5
Apr 29 2018
4.5
Version: null
lithenirish
lithenirish
Sep 21 2017
3.5
Sep 21 2017
3.5
Version: null
Miguel-Cunha
Miguel-Cunha
Aug 13 2017
5.0
Aug 13 2017
5.0
Version: null
Joseluismen
Joseluismen
May 13 2017
3.0
May 13 2017
3.0
Version: null
JIMMY2006
JIMMY2006
Apr 25 2017
5.0
Apr 25 2017
5.0
Version: null
Eric•Woehler
Eric•Woehler
Apr 24 2017
4.5
Apr 24 2017
4.5
Version: null
Mikebenda
Mikebenda
Jan 16 2017
3.0
Jan 16 2017
3.0
Version: null
marcky
marcky
Jan 9 2017
2.5
Jan 9 2017
2.5
Version: null
F-John-Cianci
F-John-Cianci
Oct 16 2016
1.0
Oct 16 2016
1.0
Version: null
Markoh
Markoh
Jun 28 2016
0.5
Jun 28 2016
0.5
Version: null
Bggale
Bggale
May 1 2016
0.5
May 1 2016
0.5
Version: null
Pypo
Pypo
Mar 14 2016
0.5
Mar 14 2016
0.5
Version: null
weeste-1
weeste-1
Jul 25 2015
4.0
Jul 25 2015
4.0
Version: null
Hilbo60
Hilbo60
Mar 4 2015
4.5
Mar 4 2015
4.5
Version: null
WetNet
WetNet
Mar 4 2015
5.0
Mar 4 2015
5.0
Version: null
Moogan
Moogan
Mar 4 2015
5.0
Mar 4 2015
5.0
Version: null
StrictlyBagel
StrictlyBagel
Mar 3 2015
3.0
Mar 3 2015
3.0
Version: null
macbond
macbond
Mar 3 2015
5.0
Mar 3 2015
5.0
Version: null
Jcmyers87
Jcmyers87
Nov 19 2014
5.0
Nov 19 2014
5.0
Version: null
MOTOWNMAN
MOTOWNMAN
Sep 28 2014
5.0
Sep 28 2014
5.0
Version: null
P1H0
P1H0
Sep 15 2014
1.0
Sep 15 2014
1.0
Version: null
Jazzyguy
Jazzyguy
Sep 14 2014
5.0
Sep 14 2014
5.0
Version: null
Emile-b
Emile-b
Sep 13 2014
5.0
Sep 13 2014
5.0
Version: null
B-Jefferson-Le-Blanc
B-Jefferson-Le-Blanc
Sep 13 2014
5.0
Sep 13 2014
5.0
Version: null
bcasey
bcasey
Sep 13 2014
1.0
Sep 13 2014
1.0
Version: null
Eamonn-f7aaaaa5
Eamonn-f7aaaaa5
Mar 18 2014
2.5
Mar 18 2014
2.5
Version: null
Drxaz
Drxaz
Jan 23 2014
2.5
Jan 23 2014
2.5
Version: null
WalterT8575
WalterT8575
Dec 16 2013
5.0
Dec 16 2013
5.0
Version: null
Lightning
Lightning
Dec 10 2013
3.0
Dec 10 2013
3.0
Version: null
RavenNevermore
RavenNevermore
Dec 8 2013
5.0
Dec 8 2013
5.0
Version: null
Abramurkwian
Abramurkwian
Nov 16 2013
5.0
Nov 16 2013
5.0
Version: null
Purps
Purps
Nov 5 2013
0.5
Nov 5 2013
0.5
Version: null
Dejmac
Dejmac
Nov 3 2013
5.0
Nov 3 2013
5.0
Version: null
TAOGde
TAOGde
Nov 3 2013
4.5
Nov 3 2013
4.5
Version: null
Ron-Magness
Ron-Magness
Dec 4 2012
5.0
Dec 4 2012
5.0
Version: null