Alkasir 2.0
 for Mapping and Circumventing Cyber Censorship

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A cross-platform, open-source and robust website censorship circumvention tool that also maps censorship patterns around the world.

With its split-tunneling feature, Alkasir 2.0 can optimize bandwidth consumption to provide better speed compared to many other circumvention tools.

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About Alkasir 2.0

Alkasir  is the English transliteration of الكاسر, which is the Arabic word for ‘the circumventor’ or ‘the breaker’ as a way to metaphorically signal its main task of breaking through digital firewalls and allowing users access to blocked websites.

It was originally developed by Walid Al-Saqaf, a Yemeni software developer who had been subjected to censorship himself and decided to start a movement to confront and map censorship in the Arab world, which explains the source of its naming.

Today however, Alkasir allows users around the world to circumvent (bypass) censorship of URLs and simultaneously, helps keep track of patterns of URL blocking. It is predominantly used by persons in countries where there is censorship of political content such as news, opinion articles, blog entries, forum discussions, political videos, etc., but can also be used in any other country.

The first version of Alkasir was launched in May 2009 as a Windows close-source application and ever since, it has grown and expanded in its new generation Alkasir 2.0 to become an open-source multi-platform solution that can work on MS Windows, MacOS, and Linux.

Click on the media below to learn more about the history of Alkasir and why Al-Saqaf created it

Main features of Alkasir 2.0

SPEED & RELIABILITY
 Efficient & optimized bandwidth usage

Unlike those of conventional circumvention tools, alkasir’s servers are quicker in response and transfer time because they are only activated for blocked websites. Furthermore, the servers are optimized to ensure that even if a request to a website on the server was sent by some sort of error, this request gets dropped at the server side of the circumvention process. Overall, this reduces the burden on alkasir’s proxy servers as they will have plenty of time to serve a much larger number of users with fewer resources compared to conventional circumvention tools.

INFORMATION
 Keeps you informed

One of the unique features of alkasir is its ability to keep you informed about which URLs are still blocked and which are not. The automatic update built-in feature of alkasir makes allows it to track if any previously blocked URLs have been unblocked and removes it automatically from its database locally on the computer and on the database. Hence, it serves as a source of information about censorship patterns.

LESS DETECTABLE
 Less prone to interception in day-to-day access

If you were using a conventional circumvention solution, then all your traffic goes through the proxy even if it were for non-blocked websites. For example, if you were accessing your web email (gmail, yahoo mail, etc.), your online bank account, or doing shopping online, all the data between you and those websites are needlessly -and perhaps dangerously- being channeled through a third party. If those circumvention programs intentionally store your IP address and personal information, that is even more of a concern, especially if the servers of those programs get compromised.

FOR A CAUSE
 For free speech & advancing knowledge

Alkasir is a software developed for the promotion of freedom and knowledge and does that for free. The software does not require the display of advertisements, nor does it require subscription payments. The program’s ability to track censorship of individual ISPs in every country of the world makes it a unique research tool to academically study the trends of censorship worldwide and hence, contributes to knowledge by presenting verifiable empirical data on censorship that is collected with the help of thousands of alkasir users around the globe.

OPEN-SOURCE
 By the community, for the community

Alkasir 2.0 is open-source and its code is available for access directly in GitHub. We see it as important to contribute to available open-source circumvention solutions to introduce new ideas and creative solutions to the ongoing problem of censorship online. Please consider participating with your thoughts and skills if you are a software developer.

Meet the Team

Walid Alsaqaf, PhD
 Founder & Admin

Walid Al-Saqaf founded Alkasir as a way to circumvent censorship of his own website YemenPortal.net, which was blocked in 2008 by the government of his homeland Yemen. Since then, he has been actively promoting online free speech and doing Internet-related research with a focus on freedom of expression. Currently, Walid’s day job is a postdoctoral researcher at Stockholm University’s Department of Media Studies and is also a member of the board of trustees of the Internet Society.

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Thomas Frössman
 Developer

As a Stockholm-based software developer and hacker culture enthusiast and with a passion for music, Thomas has been involved in software programming since the late 1980s. Before he started working on the design and implementation of Alkasir 2.0 through his current employer 23 Critters, Thomas was part of the Snowfish team, a music discovery service that was bought by Spotify and integrated into the main application.

Download Alkasir 2.0

To download and run the application, kindly take the following steps in the given order:

  1. Ensure that you have Chrome browser installed on your device. If you don’t have it, you can get it from the official website here.
  2. Download the appropriate binary for your operating system from the below links, which are updated with the latest release. If you have Javascript disabled, you can download the appropriate file directly from Alkasir’s GitHub repo here.
  3. Click on the downloaded compressed file to extract the single executable file (named Alkasir.app on Mac, alkasir.exe on Windows and alkasir on Linux).
  4. Start the Alkasir application and ensure that it is working by verifying that the icon on the system tray exists and is red in color.
  5. Click on the red tray icon and choose “Open in web browser”. If the page does not open in Chrome you need open it manually in Chrome by going to http://127.0.0.1:8899/#/ .
  6. Follow the setup instructions shown in the web browser page. This will include the installation of Alkasir’s Chrome browser extension.
  7. Verify that the Chrome extension icon is not grayed out. It should be red in color. If it is red, then congrats! Now you can report blocked websites and access them!

Important note: Alkasir 2.0 is offered free of charge to expand freedom of expression. It is therefore discouraged to use it to access bandwidth-consuming websites (e.g, pornography) or torrents or engage in any illegal activity. Please read the license agreement carefully before proceeding with the download.

If you are unable to access the website in or the above links, you can always send an email to [email protected] to get access to the software via email.

Copyright © 2025 Alkasir. All rights reserved