Last updated
Cliqz browser start page.png
Cliqz browser start page
Developer(s) Cliqz GmbH
Initial release2015;6 years ago (2015)
Stable release(s) [±]
Android1.9.7 / April 4, 2020;12 months ago (2020-04-04) [1]
iOS3.6.3 / June 30, 2020;9 months ago (2020-06-30) [2]
Desktop1.38.0 / July 22, 2020;8 months ago (2020-07-22) [3]
Repository OOjs UI icon edit-ltr-progressive.svg
Written in C, C++, JavaScript, XML User Interface Language, XML Binding Language, Rust
Operating system Windows 7 or later, macOS, Linux, RISC OS, Android, iOS
search4tor7txuze.onion Tor-logo-2011-flat.svg (Accessing link help) [4]

Cliqz was a privacy-oriented web browser and search engine developed by Cliqz GmbH and majority-owned by Hubert Burda Media. It was available as a desktop and mobile web browser as well as an extension for Firefox itself. [5] [6]



It is a fork of the Firefox web browser with privacy-oriented changes, among which are a crowdsourced anti-tracking mechanism and an in-house search engine embedded within the browser, utilizing its own index of web pages to produce suggestions within the address bar dropdown menu rather than on separate pages. The browser's developers argued that other privacy-focused search engines may still pass the user's IP address to third-party search providers.[ citation needed ]


In August 2016, Mozilla, the developer of Firefox, made a minority investment in Cliqz. Cliqz plans to eventually monetize the software through a program known as Cliqz Offers, which will deliver sponsored offers to users based on their interests and browsing history. However, these recommendations will be processed locally based on a remote repository of offers, with no personally identifiable data sent to remote servers. [6]

On 15 February 2017, Cliqz International GmbH, a wholly owned subsidiary of Cliqz GmbH, acquired the privacy-oriented browser extension Ghostery. [7] [8]

On 29 April 2020, Cliqz announced it will shut down its browser and search engine. [9] Subsequently, the search engine - called Tailcat - was acquired by Brave. [10] As of March 2021, a browser called Ghostery Dawn was reported to be under development (beta version). [11]

Integration with Firefox

On 6 October 2017, Mozilla announced a test where approximately 1% of users downloading Firefox in Germany would receive a version with Cliqz software included. The feature provided recommendations directly in the browser's search field, including for news, weather, sports, and other websites, based on the user's browsing history and activities. The press release noted that "Users who receive a version of Firefox with Cliqz will have their browsing activity sent to Cliqz servers, including the URLs of pages they visit," and that "Cliqz uses several techniques to attempt to remove sensitive information from this browsing data before it is sent from Firefox." [12]

According to the Firefox support website, this version of Firefox collects and sends data to the Cliqz corporation including text typed in the address bar, queries to other search engines, information about visited webpages and interactions with them including mouse movement, scrolling, and amount of time spent; and the user's interactions with the user interface of the Cliqz software. Interaction data collected and sent to the Mozilla corporation includes among other things, counts of visits to search engine pages, which search engines are used, and a Cliqz identifier. The data collection is enabled by default; users must actively opt-out if they do not wish the data to be transmitted. [13]

iOS app

In 2018, Cliqz released a version of their browser for iOS called Lumen. It natively leveraged Cliqz's search engine, Human Web, and supported ad-blocking and other privacy features, like an optional built-in VPN with access to 25 countries. The VPN network was owned and managed as part of a partnership with FoxyProxy. Lumen was financially profitable, but was discontinued on May 1, 2020 because of changing directors at Cliqz.

Related Research Articles

Web browser Software for using the World Wide Web

A web browser is application software for accessing the World Wide Web. When a user requests a web page from a particular website, the web browser retrieves the necessary content from a web server and then displays the page on the user's device.

Firefox Free and open-source web browser by Mozilla

Firefox Browser, also known as Mozilla Firefox or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. Firefox uses the Gecko layout engine to render web pages, which implements current and anticipated web standards. In 2017, Firefox began incorporating new technology under the code name Quantum to promote parallelism and a more intuitive user interface. Firefox is officially available for Windows 7 or newer, macOS, and Linux. Its unofficial ports are available for various Unix and Unix-like operating systems including FreeBSD, OpenBSD, NetBSD, illumos, and Solaris Unix. Firefox is also available for Android and iOS. However, the iOS version uses the WebKit layout engine instead of Gecko due to platform requirements, as with all other iOS web browsers. An optimized version of Firefox is also available on the Amazon Fire TV, as one of the two main browsers available with Amazon's Silk Browser.

Comparison of web browsers

The following tables compare general and technical information for a number of web browsers.

Mozilla Corporation American software company

The Mozilla Corporation is a wholly owned subsidiary of the Mozilla Foundation that coordinates and integrates the development of Internet-related applications such as the Firefox web browser, by a global community of open-source developers, some of whom are employed by the corporation itself. The corporation also distributes and promotes these products. Unlike the non-profit Mozilla Foundation, and the Mozilla open source project, founded by the now defunct Netscape Communications Corporation, the Mozilla Corporation is a taxable entity. The Mozilla Corporation reinvests all of its profits back into the Mozilla projects. The Mozilla Corporation's stated aim is to work towards the Mozilla Foundation's public benefit to "promote choice and innovation on the Internet."

Google Analytics Web analytics service from Google

Google Analytics is a web analytics service offered by Google that tracks and reports website traffic, currently as a platform inside the Google Marketing Platform brand. Google launched the service in November 2005 after acquiring Urchin.

NoScript is a free software extension for Mozilla Firefox, SeaMonkey, other Mozilla-based web browsers and Google Chrome, created and maintained by Giorgio Maone, an Italian software developer and member of the Mozilla Security Group.

WOT Services Website reputation service

WOT Services is the developer of MyWOT, an online reputation and Internet safety service which shows indicators of trust about existing websites. The confidence level is based both on user ratings and on third-party malware, phishing, scam and spam blacklists. The service also provides crowdsourced reviews, about to what extent websites are trustworthy, and respect user privacy, vendor reliability and child safety.

Opera (web browser) freeware web browser using the Blink browser engine

Opera is a multi-platform web browser developed by Opera Software. Opera is a Chromium-based browser. It distinguishes itself from other browsers through its user interface, functionality, and other features.

WebRTC is a free, open-source project providing web browsers and mobile applications with real-time communication (RTC) via simple application programming interfaces (APIs). It allows audio and video communication to work inside web pages by allowing direct peer-to-peer communication, eliminating the need to install plugins or download native apps. Supported by Apple, Google, Microsoft, Mozilla, and Opera, WebRTC specifications have been published by the World Wide Web Consortium (W3C) and the Internet Engineering Task Force (IETF).

Ghostery is a free and open-source privacy and security-related browser extension and mobile browser application. Since February 2017, it has been owned by the German company Cliqz International GmbH. The code was originally developed by David Cancel and associates.

Qihoo 360

Qihoo 360, full name Qihoo 360 Technology Co. Ltd., is a Chinese internet security company known for its antivirus software, Web browser, and mobile application store. It was founded by Zhou Hongyi and Qi Xiangdong in June 2005. Qihoo 360 have ≈500 million users for its Internet Security products and over 600 million users for its Mobile Antivirus products as of June 2014.

Mozilla Free and open-source software community, developer of Firefox and Thunderbird

Mozilla is a free software community founded in 1998 by members of Netscape. The Mozilla community uses, develops, spreads and supports Mozilla products, thereby promoting exclusively free software and open standards, with only minor exceptions. The community is supported institutionally by the not-for-profit Mozilla Foundation and its tax-paying subsidiary, the Mozilla Corporation.

Evidon is a New York City-based company dealing in enterprise marketing analytics and compliance services.

Qwant Search engine

Qwant is a French search engine, launched in July 2013 and operated from Paris. It is one of the few EU-based search engines with its own indexing engine. It claims that it does not employ user tracking or personalize search results in order to avoid trapping users in a filter bubble. The search engine is available in 26 languages.

Firefox for iOS free and open-source iOS web browser by Mozilla

Firefox for iOS is a free and open-source web browser from Mozilla, for the Apple iPhone, iPad and iPod Touch mobile devices. It is the first Firefox-branded browser not to use the Gecko layout engine as is used in Firefox for desktop and mobile. Apple's policies require all iOS apps that browse the web to use the built-in WebKit rendering framework and WebKit JavaScript, so using Gecko is not possible. Firefox for iOS supports Firefox Sync and is able to sync Firefox's browsing history, bookmarks, and recent tabs.

Brave (web browser) Free and open-source web browser based on Chromium

Brave is a free and open-source web browser developed by Brave Software, Inc. based on the Chromium web browser. It blocks ads and website trackers, and provides a way for users to send cryptocurrency contributions in the form of Basic Attention Tokens to websites and content creators along with the ability to keep the cryptocurrency they earned.

Firefox Focus is a free and open-source privacy-focused browser from Mozilla, available for Android and iOS smartphones and tablets. Firefox Focus was initially a tracker-blocking application for mobile iOS devices, released in December 2015. It was developed into a minimalistic web browser shortly afterwards. However, it can still work solely as a tracking-blocker in the background of the Safari browser on Apple devices.

Bitwarden Open-source password manager

Bitwarden is a free and open-source password management service that stores sensitive information such as website credentials in an encrypted vault. The Bitwarden platform offers a variety of client applications including a web interface, desktop applications, browser extensions, mobile apps, and a CLI. Bitwarden offers a cloud-hosted service as well as the ability to deploy the solution on-premises.

Mozilla VPN

Mozilla VPN is an open-source virtual private network web browser extension, desktop application, and mobile application developed by Mozilla. It launched in beta as Firefox Private Network on September 10, 2019, and officially launched on July 15, 2020 as Mozilla VPN.


  1. "Cliqz - the Privacy Browser - Apps on Google Play". Google Play Store . 4 April 2020. Retrieved 28 April 2020.
  2. "Cliqz Browser on the App Store". iOS App Store . 30 June 2020. Retrieved 24 July 2020.
  3. "Releases · cliqz-oss/browser-core". GitHub . Retrieved 24 July 2020.
  4. "Cliqz Search as an Onion Service". Cliqz. 5 December 2019.
  5. Lomas, Natasha (15 February 2017). "Private search browser Cliqz buys Ghostery ad-tracker tool". TechCrunch. Retrieved 16 February 2017.
  6. 1 2 Lomas, Natasha (23 August 2016). "Mozilla invests in Germany's Cliqz, a private search browser". TechCrunch. Retrieved 16 February 2017.
  7. Vincent, James (15 February 2017). "Ghostery has been bought by the developer of a privacy-focused browser". The Verge. Retrieved 15 February 2017.
  8. Ghostery Team (15 February 2017). "Ghostery is Acquired by Cliqz! - Ghostery". Retrieved 16 February 2017.
  9. Stommel, Dorothee (29 April 2020). "Cliqz closes areas for browser and search technologies". Retrieved 30 April 2020.
  10. "Brave acquires search engine to offer the first private alternative to Google Search and Google Chrome on both mobile and desktop". Brave website. Brave Software, Inc. 3 March 2021. Retrieved 21 March 2021.
  11. "Ghostery Browser". Ghostery. Cliqz International GmbH. Retrieved 21 March 2021.
  12. Osborne, Charlie (9 October 2017). "Mozilla pilots Cliqz engine in Firefox to slurp user browsing data". ZDNet . Retrieved 5 November 2017.
  13. Savage, Joni. "Cliqz Recommendations in Firefox". Mozilla Support. Archived from the original on 7 October 2017. Retrieved 5 November 2017.