# Why is my folder showing less data than its sub-folders? (Win 10)

**URL:** https://boards.straightdope.com/t/why-is-my-folder-showing-less-data-than-its-sub-folders-win-10/817270
**Category:** Factual Questions
**Created:** [July 4, 2018, 6:05am UTC](https://boards.straightdope.com/t/why-is-my-folder-showing-less-data-than-its-sub-folders-win-10/817270 "2018-07-04T06:05:31Z")
**Posts on this page:** 8
**Page:** 1

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### Author: ![Atomic\_Alex](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/atomic_alex/32/175_2.png) [@Atomic\_Alex](https://boards.straightdope.com/u/Atomic_Alex)
#### Post date: [July 4, 2018, 6:05am UTC](https://boards.straightdope.com/t/why-is-my-folder-showing-less-data-than-its-sub-folders-win-10/817270/1 "2018-07-04T06:05:31Z")

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I’m a bit curious about this but also kind of worried the data has been corrupted.

I have a lot of files saved under a folder title ‘Misc’, on right-clicking Win 10 reports that its 11.7 GB in size. However it should be a lot larger than that, on opening it and checking one of the first sub-folders is reporting that it itself contains 16.3 GB of data.

How can a sub-folder be larger than the folder containing it? Am I somehow channeling the Tardis?

Thanks in advance!

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### Author: ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)
#### Post date: [July 4, 2018, 6:30am UTC](https://boards.straightdope.com/t/why-is-my-folder-showing-less-data-than-its-sub-folders-win-10/817270/2 "2018-07-04T06:30:34Z")

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Have you enabled file compression? Is the subfolder on the same partition as the main folder or is it a linked folder?

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### Author: ![Atomic\_Alex](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/atomic_alex/32/175_2.png) [@Atomic\_Alex](https://boards.straightdope.com/u/Atomic_Alex)
#### Post date: [July 4, 2018, 6:39am UTC](https://boards.straightdope.com/t/why-is-my-folder-showing-less-data-than-its-sub-folders-win-10/817270/3 "2018-07-04T06:39:18Z")

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> [@Quartz](#):
>
> Have you enabled file compression? Is the subfolder on the same partition as the main folder or is it a linked folder?

No file compression, and its just saved directly onto a portable hard-drive _(sorry I’m not really tech-oriented)_.

There is definitely something odd going on though, I checked the size of another folder and its now at 19 TB and counting.

Its a 2 TB drive.

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### Author: ![SmartAleq](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/smartaleq/32/163_2.png) [@SmartAleq](https://boards.straightdope.com/u/SmartAleq)
#### Post date: [July 4, 2018, 6:50am UTC](https://boards.straightdope.com/t/why-is-my-folder-showing-less-data-than-its-sub-folders-win-10/817270/4 "2018-07-04T06:50:41Z")

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Right click on it, select “Properties” and look at the file size there. If you haven’t done this in a while and have been adding stuff to the folder it can sometimes take a minute or two to actually look over the file and figure out the actual size of it. I had a huge music folder that was saying it was about a third of what was in there, then when I looked at its properties it changed the file size and afterward would report the accurate size on mouseover.

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### Author: ![Atomic\_Alex](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/atomic_alex/32/175_2.png) [@Atomic\_Alex](https://boards.straightdope.com/u/Atomic_Alex)
#### Post date: [July 4, 2018, 3:31pm UTC](https://boards.straightdope.com/t/why-is-my-folder-showing-less-data-than-its-sub-folders-win-10/817270/5 "2018-07-04T15:31:47Z")

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> [@SmartAleq](#):
>
> Right click on it, select “Properties” and look at the file size there. If you haven’t done this in a while and have been adding stuff to the folder it can sometimes take a minute or two to actually look over the file and figure out the actual size of it. I had a huge music folder that was saying it was about a third of what was in there, then when I looked at its properties it changed the file size and afterward would report the accurate size on mouseover.

Thanks, tried this and its still reporting inaccurately though. As long as it isn’t destroying my files though I guess I’ll just have to live with it!

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### Author: ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)
#### Post date: [July 4, 2018, 7:21pm UTC](https://boards.straightdope.com/t/why-is-my-folder-showing-less-data-than-its-sub-folders-win-10/817270/6 "2018-07-04T19:21:12Z")

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Is it possible those folders are symlinks or Junction points? That would mean that the actual folder content is stored elsewhere.

If I were you, I’d back up the entire folder to another disk drive, make sure the backup is good, then replace the original with the backup. Hopefully that will fix the issue, preventing other possible problems in the future.

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### Author: ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)
#### Post date: [July 4, 2018, 9:16pm UTC](https://boards.straightdope.com/t/why-is-my-folder-showing-less-data-than-its-sub-folders-win-10/817270/7 "2018-07-04T21:16:10Z")

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I know that at this stage Windows/NTFS file system errors are uncommon, but I’d do a chkdsk just to be sure.

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### Author: ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)
#### Post date: [July 5, 2018, 10:50am UTC](https://boards.straightdope.com/t/why-is-my-folder-showing-less-data-than-its-sub-folders-win-10/817270/8 "2018-07-05T10:50:29Z")

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Does Win10 ever report files correctly? Quick answer: No.

Those numbers that you see use caching and indexing and WTFery. Earlier versions of Windows had a 3 second limit on how long they would work on calculating folder sizes: Win10 has God-only-knows further optimizations.

(Also, in the final analysis “folder size” is not a clearly defined quality: you files may be located somewhere else.)

I find it _extremely annoying_ when Windows can’t give me meaningful folder size information. _I do not attribute it to disk error or NTFS corruption._ That is _almost never_ the case.
