File Extension Database

Open PAC File

PAC extension files can be used in various applications and formats, some of them described below.

Proxy Auto-Config File

A PAC file extension, in this particular case, is a configuration file used by web browsers to select a suitable proxy server.

The PAC contains one or more JavaScript functions with one called FindProxyForURL, which defines the rules for choosing a proxy server based on a given URL.

But what is a proxy?

A proxy server is a server application that acts as an intermediary between a client requesting a resource and the server providing that resource.

PAC files are used to control and load balance Internet traffic, especially in corporate environments.

PAC files are activated in web browsers by entering the URL of the PAC file in the proxy connection settings, or by using the Web Proxy Auto-Discovery (WPAD) protocol.

When run, a PAC file returns a string containing one or more proxy server URLs.

PAC files are usually hosted on a web server and should have a PAC file name extension, filename.pac.

Since PAC files contain the configuration in plain text, it is possible to use a text editor such as Geany or Apple TextEdit to view or modify the files.

PAC Subtitles File

Another quite interesting application for a PAC file is as a subtitle format, being a proprietary format created by Screen Subtitling Systems.

The PAC extension file is used to sync closed captions with a video timeline, and can be edited with subtitle editing software such as EZTitles and converted to more standard formats, including SRT and SUB.

SBStudio II Song File

In this section, PAC file is a song format, called PAC or package file, used by SBStudio.

SBStudio is a graphical development environment used to create and test StreamBase applications.

The PAC file is made up of data blocks that store song information and audio data.

Software to open and work with a PAC file

Due to the great difference between the types of formats associated with the PAC extension, it is necessary to keep in mind the format of it, in order to use the most suitable software package.

How Can I Open PAC File on Windows

We researched and learned that the best way to open PAC file is to find a PAC file in question in Windows OS File Explorer and double click on it to launch the corresponding application.
If a PAC file is not opened in an application and you instead get a "Windows can't open a file" error message you should try looking for an application which can open the file in question.
If you know the application which can open PAC file then run it and see if there is a File->Open main menu option in the application.
If you don't know the application which function as PAC file opener then try to search online for "PAC viewer", "application to open PAC file" or "open PAC file" queries in the search engine you like.
Install the application you found and check if it can open PAC file

How Can I Open PAC File on Mac OS

We recommend to find a PAC file in question in Mac OS Finder and double click on it to launch the corresponding application.
If a PAC file is not opened in a Mac OS application and you instead get a "There is no application set to open the file" error message you can click on "Search App Store" in the error dialog and Mac OS will show you applications compatible with PAC file.
If you know the Mac OS application which can work as PAC file opener you can choose the "Choose Application..." option in the error box to associate the file extension and open PAC file in it.
If you don't know the application which can open PAC file then try to search for "PAC viewer", "application to open PAC file" or "read PAC file" queries in the online search engine you like.
Install the application you found and check if it can read PAC file

How Can I Open PAC File on Android

If you downloaded a PAC file on Android device you can open it by following steps below:

In the Android apps list on your Android device find "My Files" or "File manager" app and tap to start it.
Tap on "Downloads" folder inside the app.
You should see your downloaded PAC file in that folder.
Tap on the file. If Android device supports opening the file you downloaded it will open in the corresponding app.
If file does not open you can look for the corresponding app that can open the file by searching Android App Store for the "PAC".
If you cannot open the file with the apps from Android App Store it is possible that the file could only be opened on desktop platforms such as Windows or Mac OS. Try searching for "PAC viewer", "PAC file reader" online and see if any desktop applications can open it.
It is also possible that the file you downloaded is outdated and is no longer supported.

How to Open PAC File on iPhone or iPad

To open PAC File on iOS device follow steps below:

We advies to open Files app on your iPhone or iPad device. You can find it by swiping down on the home screen and typing "Files" in the search bar.
Tap on the Downloads folder on the Files app home screen.
You will see all files that you recently downloaded. Tap on the PAC file to view it.
If you have the right app that can open it it will automatically launch and open your file.
If you don't have the app which can open it you need to serch Apple app store for "PAC". This way you can find apps which can open PAC files.
If this doesn't help it is possible that your file could be opened only by the desktop application. To find an app which can open it on desktop look for "PAC viewer" or "PAC file" online in your favorite search engine.

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