I'm putting together a list of drive testing and repair tools for reference. This list is not complete because I'm only listing products that I'm either familiar with and/or generally have a good reputation. This doesn't mean there aren't other tools out there, and I'm hoping that we can put together a list of drive tools, and maybe in a different thread, a list of hardware testing tools. There are some similar lists on the web and even in different threads on this site, but they seem dated, and a lot of the tools in those reviews have been updated and enhanced. Please feel free to chime in with other tools and/or features for any of the tools I've listed that I might have missed. The purpose of this thread is **not** to review them, because everyone will have a different idea about what's good and bad. Additionally, almost all of the tools are different from one another, although some may have overlapping functionality. The purpose is to generally describe what the tools do. PRODUCTS AND LINKS IN ALPHABETICAL ORDER (PRICE): Disk Tools Pro ($79.99) http://www.macwareinc.com/products/mac-utilities/disktools-pro.html Added 4/11/14 Disk Utility, diskutil (FREE, comes with OS) http://www.apple.com Comes with OS X Disk Warrior ($99.00) http://www.alsoft.com/diskwarrior Drive Genius($99.00) http://www.prosofteng.com/products/drive_genius.php TechTool Pro ($99.99) http://www.micromat.com/techtoolpro Scannerz with Phoenix and FSE-Lite, Scannerz Lite ($39.95, $21.95 respectively) http://www.scsc-online.com/Scannerz.html This was updated on 6/27/13 because they added a product called "Phoenix" to the package, with a second update on 8/15/13 because they added another product called "Performance Probe" to it. smartmontools(FREE, open source) http://sourceforge.net/apps/trac/smartmontools/wiki SmartReporter ($4.95, but FREE version exists) http://www.corecode.at/smartreporter/ PRODUCTS BY PRICE (LOW TO HIGH): Disk Utility, diskutil (FREE, comes with OS) Smartmon Tools (FREE, Open Source) SMARTReporter ($4.95 for commercial version, but an older version is FREE) Scannerz Lite ($21.95) Scannerz with Phoenix and FSE-Lite ($39.95) Disk Tools Pro ($79.99) Disk Warrior ($99.00) Drive Genius ($99.00) TechTool Pro ($99.99) Tools can be broken down into two classes: General or Multi-purpose Tools Specific Tools My observation has been that the General or Multi-Purpose Tools do a (hopefully!) decent job of doing many different things, whereas those categorized as Specific Tools focus on doing a limited number of tasks, but do it above and beyond what the general purpose tools have to offer. The tools in the list above can be broken down as follows: General/Multi-Purpose Tools Dist Tools Pro Disk Utility, diskutil Drive Genius TechTool Pro Specific Tools Disk Warrior Scannerz with Phoenix and FSE-Lite, Scannerz Lite Smartmon Tools SMARTReporter Product Descriptions (alphabetical order) Disk Tools Pro - This is a multifunctional tool that is advertised as doing the following: Mac defrag to defragment your files Create bootable Mac backups Find and fix bad disk sectors on your Mac Repair volumes Receive S.M.A.R.T. alerts Utility to test disk integrity Benchmark your volumes Analyze drive capacity Repair damaged preference files Monitor your CPU Find and repair broken aliases I'm not familiar with this tool, but if you follow the thread down to the post dated Feb. 7, 2014 by giffut he has a more detailed write up. Disk Utility, diskutil - Disk Utility is the tool provided with OS X to configure drives and volumes, and do limited repair work on drives. It has a command line version named "diskutil" that many people are not aware of. Both tools can do the following: Partition, format, or repartition a drive Mount and unmount drives and volumes Create and manage disk images Create an Apple RAID Enable/disable journalling Correct and/or verify indexing Restore a drive Zero out a drive or unused portions of a drive Verify and/or correct permissions settings on a drive The command line version (diskutil) is more capable than the GUI version (Disk Utility.) Currently, configuring CoreStorage must be done using diskutil, but I assume this will change in the future. Neither tools perform surface scans on a drive, and when one uses the "Repair Disk" option, it's working on the index files, not actual drive problems. I would strongly recommend that anyone interested open up a Terminal.app session and type "man diskutil" to see its full functionality. Disk Warrior - Disk Warrior has one purpose and one purpose only: To fix indexing problems on a hard drive that Disk Utility and diskutil cannot and in the process, recover what may be lost files. If you've ever had problems booting your system, run Disk Utility on it, and it said that the drive could not be repaired and you should back up what you can, reformat, and then re-install the data, it's likely your index files which locate the data on the drive have become corrupt. This is one of the major types of problems that Disk Warrior can fix, assuming the drive itself isn't damaged. This software attempts to create a new set of index files based on what's already on the drive and install it in place of the original index. The only caveat is that if you're mixing Windows (or other non-Mac formats) with it, it likely won't be able to help you. As another poster has pointed out, this product still uses a 32 bit format and may have problems with some very large drives. (See post by TVALLEAU on April 14, 2014) Drive Genius - Drive Genius is a multi-purpose tool that is advertised as doing the following: SMART Monitoring Defragmentation Disk services such as formatting, repartitioning, and zeroing a drive Data recovery Directory rebuild (64 bit) Basic surface scanning Index and permissions repair Find duplicate files on the hard drive Do performance testing on a drive Drive cloning Directory reconstruction Some of the tasks Drive Genius performs are obviously available using Disk Utility or its command line counterpart, diskutil, however, others, such as defragmentation, finding duplicate files on a drive, surface scanning, performance testing, and drive cloning are not. I would view this tool as a superset replacement, for the most part, for Disk Utility. TechTool Pro - TechTool Pro is a multi-purpose tool that is advertised as doing the following: SMART Monitoring Basic surface scanning System optimization Memory tests Video tests Drive cloning Index repair and file system/directory recovery (64 bit) Defragmentation Network monitoring This tool has similarities and differences with the other multi-purpose tools, Drive Genius, Disk Utility, and diskutil. Whereas Drive Genius tends to focus more on the drive and what's on it, this tool tends to be more system hardware oriented because it can perform hardware tests on RAM, the video subsystem, as well as the drive, and can do some LAN monitoring Scannerz with Phoenix and FSE-Lite, Scannerz Lite - Scannerz with Phoenix, Performance Probe, and FSE or FSE-Lite is a hard drive and system diagnostic package that is used to find hard drive problems that are either emerging or already exist, and can isolate other problems that act like hard drive problems or cause system bottlenecks. These guys keep adding stuff to the package as free updates and this is the third time I've needed to update what they have. Scannerz is the drive scanning tool and can identify both drive problems and other problems with the system like bad cables. FSE-Lite is a basic file system events monitor and can be upgraded to the enhanced version named FSE. Both tools can be used to track file system activity. Phoenix is a tool this company added in late June of 2013. Phoenix allows a user to extract the operating system from a working OS X bootable volume and clone it to what's called a Phoenix Boot volume, perform basic cloning, and re-install the OS from a Phoenix Boot Volume if needed. Performance Probe was added in August of 2013 and is a load monitor that can help see when a system is being loaded for some reason…it's sort of like a "performance meter" for your system. Scannerz Lite is a reduced version of Scannerz and does not include any other tools. You cannot troubleshoot anything with this as their is no cursory mode testing. It's advertised as being a tool for people that want to just find out whether or not their drive has problems. It is, however, inexpensive. The following list of advertised features will focus on Scannerz with Phoenix, Performance Probe, and FSE-Lite and any interested parties should visit the web site for details regarding the differences between Scannerz with Phoenix, Performance Probe, and FSE-Lite/FSE and Scannerz Lite. Scannerz with Phoenix and FSE-Lite is advertised as being capable of doing the following: Identification of bad sectors on a drive Identification of weak sectors on a drive Triggering SMART status updates on fault detection (drive dependent) Report SMART status failures during test (but only reports failures, not details) Identification of applications utilizing excessive file resources (via FSE-LIte/FSE) Detection of problems with cables, logic board problems or other faults Detection of performance degradation due to system problems Volume cloning via Phoenix Essentially a system restore via Phoenix OS extraction to a so called Phoenix Boot Volume Performance monitoring with Performance Probe. smartmontools - This is a set of cross platform, open source, SMART monitoring tools. These are command line tools and must be run from a Terminal.app session. The two primary tools in the package are "smartctl" which can report on SMART status of a drive instantaneously, and "smartd" which is a daemon process that can be set up to monitor the SMART status of drives periodically. The standard download is in source code and needs to be built by the user, but there are pre-built binaries on the web. The SMART reporting is extremely thorough. The product uses a database of drives that's updated periodically and may need the There are several GUI interfaces available for this, but most of them appear to be Unix/Linux oriented and likely rely on the presence of X-Windows and it's development libraries on the system. SmartReporter - There are commercial and free versions of this tool available, although the free version may be outdated. This product interacts with the OS X operating system's own SMART monitoring capabilities and then reports the output to the user. The interface is completely graphical and the tool can be set up to operate in a daemon mode to warn a user if a drive has suffered a serious SMART failure, whereas Disk Utility and diskutil will only do it when the application is actually used. A word about SMART testing: SMART testing typically isn't available on USB or FireWire drives, but it may be available on some Thunderbolt external drives and drives directly or indirectly using SATA or eSata interfaces.