iDefrag 5

Defragmentation & Optimization for Mac OS X

Download iDefrag Version 5.1.9 (13.4 MB) Buy Now $39.95 Upgrade Now $19.95

WARNING: On macOS Sierra 10.12.5, we have had a number of reports of problems, including application launch failures and system boot failures, after using the on-line modes in iDefrag. We have been unable to reproduce these issues; nevertheless, we recommend users contemplating the use of on-line defrag ensure that they have recent, working, backups, just in case. If you are affected by these problems, we would appreciate it if you could get in touch BEFORE restoring or reformatting your machine.

Users running versions of macOS prior to Sierra (10.12), please see the compatibility chart to find the correct version for your system.

New in iDefrag 5

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Why defragment?

If you use spinning disks, you’ll have noticed that over time it takes longer and longer to access your files, to start your applications and even to start your machine.

This is an unavoidable consequence of the way hard disks work. It can be made better or worse by the design of the filesystem (and, actually, in this respect your Mac’s filesystem, HFS+, is one of the best), but in the long run there’s really no way to avoid this effect.

The cause of this slow-down is fragmentation, and when it happens, you need iDefrag.

This problem largely does not affect SSDs — though they do still perform less well if files are fragmented, the difference is much smaller and for most SSD users it won’t be worth spending the time defragmenting.

Why iDefrag?

Buy iDefrag 5 now

N.B. iDefrag 5 requires Mac OS X 10.10 Yosemite (or higher). For older releases, please see here.

Pre-release versions of Mac OS X are not officially supported. They may work, or they may not.