This post was most recently updated on June 7th, 2019
It is not uncommon for you to be searching the internet for a file of a particular format/extension… and all you get is either .7z, .zip or .rar. In 99% or the cases, you already got what you want, just that, the real file has been compressed. In this article, I will be giving a comprehensive tutorial on how to extract compressed files. Archived files contain other files of which what is inside can be exactly what you need. For example, Windows Os directly uses .exe and .msi. if you search for a windows computer file on the net and you see something like “Mozilla Firefox browser for pc.zip” Then it means, Firefox.exe has been compressed into a .zip archive. in all certainty, you need to extract or decompress an archived file in order to get into the enclosed files within.
What is an “Archive/Compress File”?
According to Wikipedia, An archive file is a file that is composed of one or more computer files along with metadata. Archive files are used to collect multiple data files together into a single file for easier portability and storage, or simply to compress files to use less storage space. Archive files often store directory structures, error detection and correction information, arbitrary comments, and sometimes use built-in encryption.
On the other hand, File compression is a process of “packaging” a file (or files) to use less disk space. Compression software allows you to take many files and compress them into one file. The benefit of this is that it is smaller than the combined size of the originals.
Examples of Archive/Compressed files
Why is there a Need For File Compression/Archiving?
To Save Storage Space and Cost
Generally, when you compress files, the overall size reduces in comparison to the combined file size. For example, if the total size of the file a, B and C is 300mb, after compression into like zip or rar format, you can get 210mb or less as the combined size. Mind you, after extraction, the files return to their original sizes. Furthermore, File compression allows you to store and back up significantly more data, and faster.
Similarly, the costs of storing your data are reduced by compressing your files for storage because you can store more files in your available storage space when they are compressed.
It allows the original file extensions to be Disguised
Sometimes, hackers compress some malicious files in order to disguise it and make sure it bypasses security software. Thank goodness, many antivirus software has found a way around this. Likewise, pirated software might be renamed and compressed before being uploaded for download. This act is to beat the law. Don’t compress your files for any of the two reasons listed above. It is illegal.
To Protect and Encrypt the Files
You can also compress your file in order to protect its identity. Also, many files decompressing software have the option to password-protect files. This will add an extra layer of security to your files.
Compressing a file can help you with splitting it for easy uploading and downloading
Imagine a situation whereby you need to download a 3gb file from a slow non-resumable server. Won’t it be better if the file is split (by a file compressor) into like 200MB each for a more convenient download?. Well, if you have had to deal with slow internet, you will appreciate this better.
To effectively post files on a web page for someone else to download or to send large documents as email attachments.
Files can become corrupted when they are transferred over the internet in an uncompressed format. Transfer time is lessened when files are compressed. File compression is often a necessity for sending large documents over the internet as email attachments since most email systems limit the size of each email message. Often it is easier to compress multiple documents into one document to attach to an email message rather than attaching them one-by-one.
- To download and open files from a web page or from your email application that has been compressed.
Bandwidth and Transfer Speed
What are the drawbacks of Compressing File?
Compressed files must be uncompressed to be opened. When using file compression to send email attachments, the recipient of the message must understand how the file was compressed and have the tools to uncompress the file. Unfortunately, not everyone knows about this basic technicalities.
How to Determine whether a file is Compressed or Not?
Most compressed files have extensions indicating the format like .zip, .rar, .7z, etc. Often they have standard headers so you can tell by the first few bytes of the file.
But there is no way to be certain. Compressed and encrypted files are both statistically random and indistinguishable without knowing the compression algorithm or the encryption key.
- The first method is to check the file extension to determine if its what you are expecting or not. For example, if you are expecting a .exe file and you receive a .7zip file, then that file has probably been compressed. Similarly, once you are not sure of the extension, contact the sender and ask. Please don’t extract a file that you don’t trust the extension.
- Secondly, check the file extension and see if it falls within any compression/archiving formats such as zip, rar. 7zip, cab e.t.c. You can learn more here.
- Another way to detect if a file looks compressed is to try to compress it. If you can’t significantly reduce the size, the file is probably compressed or encrypted.
- How to rename file extensions on your phone and computer
- Using Blueftp to unzip / Extract / Decompress your zip files on Java Phones
Precautions When Dealing With Compressed Files
To learn more about archive files formats and their comparison, please read this. It is also worthy of note that .zip is the most popular and the easiest to decompress while .rar is the most secure.
- Don’t attempt to open a file archive that is very big in size on your phone, use your computer instead. There is a limit to the size of compressed files a mobile decompressor can handle. I wouldn’t try a file bigger than 4GB
- If you are downloading a compressed file over the internet, do so only from a trusted source. compressed files have both its advantages and disadvantages as blackHat hackers and white hat hackers make use of them extensively. The bottom line is that you can download a computer virus contained in an archive if you are downloading from untrusted sources. such virus mostly includes adware, malware and trojan. So please only download files that you know and need.
- Secondly, exercise caution when downloading split archive files. Test each part after download and do not wait to download all the parts before attempting to extract. For example, if you want to download a file that is 12gb in size, it is most likely it will be split into parts of like 1gb each and the format will likely be .rar or .zip. once you finish downloading the first part, try and open it with your file decompressor, once you receive a message like “some volume/parts are missing” it means the first file is healthy you can proceed. but if you receive “archive corrupt or damaged” or “enter password” please do not proceed. In case of password protected file, please get the password before you download all the parts.
- The above clues are hard and fast rules fail-safe tips that you must apply at all times before downloading any archive files.
Types of Software That can Open Compressed/Archived Files
I will arrange them in order of competence and versatility. For both mac, mac os, android os and windows.
How to extract compressed files on Windows Computers
- Windows file explorer: Don’t be surprised that Win7, win8, win10 file explorer can open zip files by default. All you need to do is to simply double click on the zip archive and it will open for you to extract.
- For windows computers I strongly recommend WinRar: Winrar can open virtually any file format
- 7-Zip(this is good when you want to open some stubborn .7z files
How to Extract Compressed files on Mac Computers
- If you are extracting a zip archive on mac, all you need to is to double click on such file. Mac from OS can extract and decompress zip files.
- However, if you want to open other more complex file archives such as .rar, cab and so on, you will need a 3rd-party file decompressor. I take pleasure in using “The Unachiver” on my Mac as it is pretty easy to use. You can download it from the App Store.
How to extract compressed files on Android Phones
- In case your Android phone comes with a pre-installed file manager app, first, attempt to use it to open your zip files. If it doesn’t work, then you can download a free 3rd party app. For the records, Samsung Galaxy phones have been opening zip files via the default file manager for a long time
- If however, you have other file archives such as RAR, you can use a 3rd-party advance android file manager to extract or decompress. My favorites are “root browser”, ES explorer” and File expert”. You can download any of this on google play store. For Android, we have many file extractor. In addition, Uc browser for Android can extract any zip or RAR file. Lastly, you can also specialised file decompressor for android such as ZAchiver, WinRar, easy unrar and so on.
How to extract compressed files on Apple iDevices Especially iPhones
- Thankfully, iOS 12 comes with a pre-installed file manager. This file manager is capable of performing some basic functions one of which is the ability to extract zip files. To do this, you need to open the “File” app on your iPhone with iOS 12. Then, navigate to the zip file you already downloaded or copied to your phone>>open it>>then click on preview content>>then swipe through the preview images
- Alternatively, go to the app store and download apps that can decompress files on iOS. One that i use often on phones that are not jailbroken is “PhoneDrive“. Of course, you have multiple options if your phone has a jailbreak. Hurry and download iFile if you already jailbreak your iDevice. Once you get the correct file, extraction is a breeze.
Steps to be Taken When Extracting a Compressed File on PC
- Drag or move or copy the file to a known location on your pc. I recommend your desktop if you are using a computer.
Like I said earlier, WinRAR is a great tool for extracting files from their compressed formats. One thing that makes WinRAR so popular is the ease of use. There are several ways to open an archive for unzipping one method is just by clicking on the file to open WinRAR and by Drag-and-dropping the file to your destination folder.
- First, select a RAR file that is part of the archive then open the file
- Select any RAR part of the archive
After you open the file, it will bring up a window showing you the details of the complete file. You can then highlight the file then drag and drop the file into the desired location.
- Drag the file to from the Win Rar window into the desired location.
- After you drag and drop the file into the desired folder, WinRAR will bring up a window showing the UnRAR process.
- When the UnRAR/UnZIP process is complete, it will leave the finished file in the destination folder. Now your file is ready to be used.
- Now you can make use of the file. the above guide is for windows computers and this same simple principle can be employed for Mac or even mobile devices using the appropriate software.