Disks and Files Utilities

( /is/apps/macos/disks-files/ (newer) and /is/apps/diskutilities/ (old, redirect to this page) )

Topics – Disks and Files Utilities

Categories of Utilities, What want to do?



d https://jandp.biz/is/search/ –

Make Image from Folder – Service

Where Find Culprits …

Sizes (…!)

Oh, what an actually quite complicated topic…!


Db: ‘Online Only’
Personal acct
Db: ‘Online Only’
Business acct
del-01-26.24min.mp4 del-01-26.24min.mp4
Db: ‘Online Only’
GUI: Finder, List view ‘1 byte’ ‘Zero bytes’ ‘1 byte’ ‘510.2 MB’ ‘Zero bytes’
GUI: Get Info ‘1 byte (4 KB on disk)’ ‘Zero bytes (compressed)’ ‘1 byte (Zero bytes on disk)’ ‘510,187,850 bytes (510.2 MB on disk)’ ‘Zero bytes (compressed)’
CLI: ll (ls -l) ‘1’ ‘0’ ‘1’ ‘510187850’ ‘0’
CLI: ll -h ‘1B’ ‘0B’ ‘1B’ ‘487M’ ‘0B’
CLI: du ‘8’ ‘0’ ‘0’ ‘996464’ ‘0’
CLI: du -h ‘4.0K’ ‘0B’ ‘0B’ ‘487M’ ‘0B’


$ ll
-rw-r–r–@ 1 johan  staff  1 Jul 31 07:01 1-byte-file.txt
$ ll -h
-rw-r–r–@ 1 johan  staff     1B Jul 31 07:01 1-byte-file.txt
$ du 1-byte-file.txt
8 1-byte-file.txt
$ du -h 1-byte-file.txt
4.0K 1-byte-file.txt


  • ‘510.2 MB’ in Finder list view
  • Finder > Get Info: 510,187,850 bytes (510.2 MB on disk)
  • And in both these cases ‘M’ stands for mega as in 1000 0000 (10-base, 10 raised to 6)
  • In terminal
    • $ ll del-01-26.24min.mp4
      -rw-r–r–@ 1 johan  staff  510187850 Nov 30  2020 del-01-26.24min.mp4
      $ ll -h del-01-26.24min.mp4
      -rw-r–r–@ 1 johan  staff   487M Nov 30  2020 del-01-26.24min.mp4
      $ du del-01-26.24min.mp4
      996464 del-01-26.24min.mp4
      $ echo $BLOCKSIZE$ (BLOCKSIZE is unset thus block size used in presentation is 512 bytes)
    • $ du -h del-01-26.24min.mp4
      487M del-01-26.24min.mp4
  • 487M comes from 510187850/1024/1024, 1024  as terminal tools commonly still uses Base-2 arithmetics, binary numeric system, = 486.5530490875, which rounds to 487 (M as in Mebibyte, in this case).
  • 996464 comes from 510187850/512 = 996,460.64453125 and as local file system at this point has a disk block size of 4K / 5+ ###another 4  basically… not figured out exactly reason
    • 996464 x 512 = 510,189,568
    • 996,460 x 512 = 510,187,520 ; 996,460.64453125
    • 510187850 – 510,189,568 = 1718



Db, Personal acct Db, Business acct
Local Online Only Local Online Only Comments
1 GUI: Finder, List view ‘375.6 MB’ ‘Zero bytes’ ‘375.6 MB’ ‘375.6 MB’
2 GUI: Get Info ‘375,582,861 bytes (375.6 MB on disk)’ ‘Zero bytes (Zero bytes on disk)’ ‘375,582,861 bytes (375.6 MB on disk)’ ‘375,582,861 bytes (Zero bytes on disk)’
3 CLI: ll (ls -l) ‘375582861’ ‘0’ ‘375582861’ ‘375582861’
4 CLI: ll -h ‘358M’ ‘0B’ ‘358M’ ‘358M’
5 CLI: du ‘733568’ ‘0’ ‘733568’ ‘0’ At least du command seems to behave as expected.
6 CLI: du -h ‘358M’ ‘0B’ ‘358M’ ‘0B’
7 Comments: Case ‘1’, ‘as expected’ Case ‘2’, zero bytes on disk makes sense but zero bytes for file size could be argued… ‘Case 1’, ‘as expected’ Case ‘3’, zero bytes on disk makes sense but showing actual file size if more helpful, useful, than zero…
  • That ‘Local’ info is remains same independently of type of Dropbox account is of course what to expect. Even having this note seems ridiculous but… Next:
  • WHY is it different info displayed depending on Personal or Business account for Online Only file…?!?
    • Personal: ‘Zero bytes (Zero bytes on disk)’
    • Business: ‘375,582,861 bytes (Zero bytes on disk)’
  • (On a Mac computer with macOS 10.13.6, High Sierra, and Dropbox ‘Version: 127.4.4265’, ‘Modified: 2021-Jul-20 Tue at 19:36’.
  • (Findings compiled here 2021-08-05)


Characteristics of file system entries

  • Logical size of file content
  • Physical size of file content
  • Logical size of file on disk
  • Physical size of file on disk

Dropbox ‘view/opinion’

Term Dropbox Clarification
“physical size” “A Smart Sync placeholder takes up approximately 0kb, this is the pysical size.”
“logical size” “The logical size of the file is the actual size of the file, if it were downloaded to the device (the size reported through your “Large File Report” is the physical size of the file). “




“First off, thanks for using our BETA versions – I guess you’ve opted in “early releases” on your Dropbox account, right?

[Kindly note that as beta builds are still in the testing process, you could experience some issues or an inconsistent experience.]

Now, as per the matter at hand, from what I see in your last screenshot this specific file is physically taking up no space (i.e. this is what the “Zero bytes on disk” means). Read on for more context:

As there are various places to see the size of a file in Finder, it’s good to know that some of these locations will display the logical size, others the physical size. A Smart Sync placeholder takes up approximately 0kb, this is the pysical size. The logical size of the file is the actual size of the file, if it were downloaded to the device (the size reported through your “Large File Report” is the physical size of the file).

To see both the logical and physical file size:
– Right click on a file/folder
– Select ‘Get info’
– In the properties window you will see the original file size, followed by the actual on-disk size:

For example:428,510 bytes (0 KB on disk)

It is important to be able to view both sizes, not just to reassure you that the file is not taking up space, but also to understand the space and speed implications of returning the file(s).

In other views of Finder, the operating system will report the logical size. For this reason you shouldn’t be concerned if it initially appears that the placeholder is taking up space. To confirm the file or folder is not taking up space, please check via the above steps. Files that are not taking up space on disk will have an icon overlay that changes from the usual green tick to the grey cloud icon, denoting that the file isn’t locally present.

Please note that third party disk management software may not read the physical size of a Smart Sync placeholder, therefore that software may not correctly report disk usage.

I hope this inforrmation helps and please let me know if there’s anything else I can do.

Community Moderator @ Dropbox


Terminal Commands, CLI Commands

  • ls – classic *NIX
  • file – also classic *NIX
  • Mac OS specific:
    • mdls
    • mdfind
    • mdutil
  • xattr – display and manipulate extended attributes
  • stat – readlink, stat – display file status




Tools for What’s Eating my Disk Space

Application Cost JRate Comments
Baseline (Gone) 0 No longer available
Disk Inventory X $0 (FOSS) 4/5 Good, a favorite
GrandPerspective $0 (FOSS) 1/5 Only boxes-display, no text
OmniDiskSweeper $0 (Free, Propr.) 4/5 Good display, easy navigate, a favorite
WhatSize $15 0/5 Doesn’t work…


[1] http://old.jandp.biz/is/apps/diskutilities/


Research into better tools to find culprits



Baseline by MildManneredIndustries – GONE


crossdirstat (FOSS) (J: 0/5)

(Tried it once, crossdirstat-2.0.0-mac on macOS 10.13 but after running for maybe an hour collecting data, ended up with showing a white window with nothing else…, why zero 0f 5 rating.)

DaisyDisk ($10)

Disk Inventory X (FOSS) (J: 4/5)

(It’s all relative, give it a 4 of 5 as among the better tools found so far, for our intended purposes of easier finding big eater culprits.)

GrandPerspective (FOSS) (J: 1/5)

  • Free, open source, weird interface – do not like.
  • grandperspectiv.sourceforge.net – home page for app
  • I.e. ONLY has graphic visualization of disk use, NO table/directory/file system entries view(s) (like e.g. Disk Inventory X above does)

OmniDiskSweeper (Free) (J: 4/5)

  • Free but not open source
  • omnigroup.com/more/
  • No graphic representation like Disk Inventory X and GrandPerspective but that is NOT a drawback in out oppinion.
  • Instead have a really easy to read and navigate file directory display of information:


WhatSize ($15) (J: 0/5)

As long as hangs and has to be Force Killed, a zero of 5.

Otherwise, not the most user-friendly user interface and probably would get 1 of 5 if worked.






OLD: Disk Utilities


Want To Application(s) Comments
Good Overview of Large Files
  • WhatSize, 1st choice
  • Baseline, 2nd choice
  • OmniDiskSweeper – basic, but FREE
WhatSize has most flexibility
See/Find What Changes Over Time
  • Baseline (only choice1)
Find Duplicates
  • Baseline (only choice1)
1 I.e. among the applications listed here.




Application price


Version/Release Info Comments
Ver. Date* Size
Baseline $20.00 v1.4.2 20081124 (mod) 8.6MB More info: (Seems gone 2020, https://www.google.com/search?q=www.mildmanneredindustries.com+baseline)

MW review v1.4.2 Dec 08, rating 4/5

GrandPerspective Free v1.0 20081222 (mod) 1.3MB open-source; only a visual graphical representation and one that neither is that easy to interpret nor that useful (as far as seen/understood so far)

– Not that useful

(MW rating: 4/5, v0.93 – MacWorld’s Byte breakdown Apr’06.)

OmniDiskSweeper Free(1) v1.7 20090224 (mod) 6.3MB (1) Free since v1.7 Feb 2009 (was $15 prior)

+ Decent util (considering it’s now Free) to get a good overview of large folders and files.

– No means to sort other than default (decending order size of folders/files).

More info: omnigroup.com/applications/omnidisksweeper.

(MW rating: 3.5/5, v1.5 – MacWorld’s Byte breakdown Apr’06; NOTE: This rating was for the for-pay version.)

WhatSize $12.99 v(10.)4.5.1 20090317 (mod) 6.4MB More info: id-design.com/software/whatsize.

(MW rating: 4/5, v10.3.9 (current per Apr09 is v(10.)4.5.1) – MacWorld’s Byte breakdown Apr’06.)


The Top Five Mac Hard Drive, Diagnostic, and Repair Utilities, Feb 23, 2007 – http://www.peachpit.com/articles/article.aspx?p=693649

  1. Prosoft’s Data Rescue II – http://prosofteng.com/products/data_rescue.php -,
  2. Also by Prosoft, Drive Genius,
  3. MicroMat’s TechTool Pro,
  4. Alsoft’s DiskWarrior
  5. AppleJack is the only open source


Hyperbolic Software Tidy Up! ($39) http://www.hyperbolicsoftware.com/TidyUp.html




Comparing 1Password – being evaluated – to Web Confidential – used for many years.

Mac OS X


Baseline OmniDiskSweeper WhatSize Comments
Product Info Apple baseline omnidisksweeper whatsize
Developer Apple mildmanneredindustries omnigroup id-design.com
Pricing incl in OS $20 Free $12.99
General comments ### Rather simple tool,

only lists size (but still better than Finder (10.5)),

no Find Duplicates, …

Version 10.5.8 1.4.2 1.7 (i) (i) = as per About information inside application

(m) = Modified time stamp as per Info (Command-I) for installed application.

Released ~2009


2009-11-24 (m) 2009-02-24 (m) 2009-03-17 (m)
since today ~5 months ago ~ 2 months ago ~ 1 month ago (This review per Fri 2009-04-17)
R&D ? ? ? ?
Application size ? 8.6 MB 6.3 MB 6.4 MB
General Use
Primarily how using From within browser.

(Application isn’t even

visible in list of open

applications. Nice!)

Application itself. 1P: adds a button – and toolbar – in web browsers and this is how accessing most commonly used features.

WC: from the application itself, limited integration with web browsers.

Starting 3 sec* 10 sec* 1Password starts significantly faster.

*) Times only to be seen relatively; on a specific Mac (Mini), with lots of applications running.


Baseline OmniDiskSweeper WhatSize Comments
# Views 4 4 1 5 ###
names 1:As Icons (Cmd-1)

2:As List (Cmd-2)

3:As Columns (Cmd-3)

4:As Cover Flow (Cmd-4)

1:List View (Cmd-1)

2:Columns View (Cmd-2)

3:Tree Map (Cmd-3)

4:Duplicates (Cmd-4)

n/a 1:Browser View (Cmd-1)

2:Outline View (Cmd-2)

3:Table View (Cmd-3)

4:BarChart View (Cmd-4)

5:PieChart View (Cmd-5)

List View, Outline View Yes (Cmd-2) Yes (Cmd-1) No Yes (Cmd-2)
Table View No No No Yes (Cmd-3) (1) (1) Including pre-defined searches
Columns View Yes (Cmd-3) Yes (Cmd-2) Yes Yes (Cmd-1)
Cover Flow View Yes (Cmd-4) No No No
Tree Map No Yes (Cmd-3) (1) No No (1) Similar to GrandPerspective’s (not in this table) view.
BarChart View No No No Yes (Cmd-4)
PieChart View No No No Yes (Cmd-5)
Duplicates View No Yes (Cmd-4) No No
Find duplicates No Yes

(but quite slow)

No No
Total space occupied by duplicates n/a No n/a n/a
Delocalization No No No Yes (Cmd-6)
Baselines, save state to see changes over time


No Yes No No Can be quite useful when trying to find out what’s eating space over time (like memory leaking applications)