is it possible to determine the uncompressed size of multiple zip files without decompressing them?

[imrandrsni]

How do I determine the uncompressed size of multiple zip files without decompressing them? i have a large amount of zip files i want to unzip, and the files will be larger than the actual zip file(s). ranging in all different sizes. and i want to buy an extra hdd for the extracted files, but i want to know the total size before purchasing the drive and unzipping them.

 

[imrandrsni]

(using windows 10 pro 64bit)

 

[USAFRet]

In Win 10, rightclick the zip file - Properties
Select Archive
You get this:

Total Length is the unzipped size.

WinRAR shows the same size if it were unpacked:

 

[bigpinkdragon286]

I suspect there is no easy way to determine total uncompressed space needed using vanilla Windows 10. You can certainly open each archive and see the size of each file, but if there is more than one file in each archive you need to manually add them all up.

With WinRAR or 7-Zip, you can get a summation of the total size within each compressed archive. Both should be available to use for free, at least temporarily.

Bear in mind, you will need extra capacity on your target drive to decompress your files due to the nature of storage devices. Files do not occupy storage locations in a perfectly efficient manner and will have overhang. Due to this, actual file size and the size on disk are often slightly different. If you're going to insist on acquiring a drive that only just holds the contents of your archives, I would up size the new drive by 5 - 10% to avoid file overhang on the disk from preventing you storing the entire contents you were expecting.

 

[Solandri]

I think OP wants to know a quick and dirty way to do this for multiple zip files. e.g. He's got a thousand zip files scattered in various subdirectories on the drive, how can he tell their uncompressed size without individually clicking on every single zip file? I don't think you can. You *should* be able to, as I believe the zip format saves the original file size as metadata. But I haven't seen a tool for accessing this metadata across multiple zip files (kinda like a windirstat for zip files).

Bear in mind, you will need extra capacity on your target drive to decompress your files due to the nature of storage devices. Files do not occupy storage locations in a perfectly efficient manner and will have overhang. Due to this, actual file size and the size on disk are often slightly different. If you're going to insist on acquiring a drive that only just holds the contents of your archives, I would up size the new drive by 5 - 10% to avoid file overhang on the disk from preventing you storing the entire contents you were expecting.

The extra overage is roughly half the cluster size (4k default for NTFS) times the number of files. So for a hundred thousand files it'd be about 200 MB. For 10 million files it'd be about 20 GB. This is one of the reasons to store folders with lots of small files as zip files. It also makes opening folders quicker if the thousands of small files are stored in a single zip file (Windows Explorer has to read things like icons for each file every time you open a folder).

Although I would suggest getting a drive at least twice as big as you need today, to future-proof yourself. Otherwise a year or two down the road you're going to be looking to buy yet another drive.

 

[USAFRet]

I think OP wants to know a quick and dirty way to do this for multiple zip files. e.g. He's got a thousand zip files scattered in various subdirectories on the drive, how can he tell their uncompressed size without individually clicking on every single zip file? I don't think you can. You *should* be able to, as I believe the zip format saves the original file size as metadata. But I haven't seen a tool for accessing this metadata across multiple zip files (kinda like a windirstat for zip files).

Right.
You might be able to write a powershell script for this, but I've not seen anything prepackaged.

Just buy a larger drive.

 

[bigpinkdragon286]

I went ahead and coded a simple solution to show the total uncompressed size for .zip files since I found the problem amusing and they are easily supported in .NET.

Anybody interested can download the utility here:

ShowZipSize

You'll most likely have to Unblock the file using Windows Explorer to run it.

 

[imrandrsni]

I went ahead and coded a simple solution to show the total uncompressed size for .zip files since I found the problem amusing and they are easily supported in .NET.

Anybody interested can download the utility here:

ShowZipSize

You'll most likely have to Unblock the file using Windows Explorer to run it.

this is almost exactly what i was looking for. thats super impressive btw. my files apparently appear to be .7z any way to select that file type with your launcher? thanks for all the replies. wow