Sleipnir (web browser)

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Developer(s) Fenrir Inc, Osaka, Japan
Stable release (January 15, 2015; 44 days ago (2015-01-15) [1]) [±]
Operating system Windows Vista, Windows 7, Windows 8 and OS X 10.6/10.7, iOS, Android, Windows Phone
Type Web browser
License Proprietary

Sleipnir is a tabbed web browser developed by Fenrir Inc. The browser's main features are customization and tab functions. It supports HTML5 and different layout engines.

The names Sleipnir and Fenrir are both animals from Norse mythology.[2][3]

Sleipnir was originally created in Japanese and then released with English and Chinese translations. Further translations are performed by volunteer translators.[4][5]

It is available for iOS, OS X, Microsoft Windows, Android and Windows Phone.


Sleipnir was originally developed by Yasuyuki Kashiwagi. In November 2004, the computer containing Sleipnir's source code was stolen.[6] In 2005, Kashiwagi established Fenrir & Co. to start development of a new version of Sleipnir. Starting with version 2, the new versions are not compatible with the original.

As of 2006 Sleipnir had 6% market share in Japan.[7]

Sleipnir was one of twelve browsers originally offered in a browser ballot screen on the EU edition of Windows 7 (and XP and Vista with an update),[8][9] so users of might choose between Internet Explorer and other browsers during the installation process.

The stable version, 5.0, was released on December 24, 2013[10] with the latest Blink engine. The latest stable version is 6.0.


In the Windows version, the browser's layout engine can be changed. Internet Explorer's Trident and Mozilla's Gecko were supported. As of version, support for the WebKit rendering engine was implemented and Gecko rendering engine support was terminated.[11] Other features include tab grouping, mouse gestures, page zooming, a search bar, Greasemonkey-like user script support, and plugin support. Bookmarks on Sleipnir can be synced with different platform, using a function called Fenrir Pass.

Sleipnir version 5 and onward introduce a proprietary text rendering visually resembling Mac OS text rendering. The feature is not mentioned in their Mac feature set.[original research?]


Sleipnir 3 for Windows: Includes tab options, tab groups, Touchpaging to flick between tabs using your mouse, and mouse gestures.

Sleipnir 2 for Windows: Sleipnir 2 features customizable functions and add-ons created by users. Sleipnir 2 is one of the few browsers to still support Windows 98.

Sleipnir 3 for Mac: Switch tabs by swiping tabs left or right-click; Operate tabs using gestures; TiledTab - Pinch-in on the TrackPad to view a list of tabs; Hold And Go - Hold down on a link to open in the background; Ad Block; Tab groups for managing tabs; Sync bookmarks with other devices using Fenrir Pass; The standard full-screen with OS X Lion<unclear>[12]

Sleipnir Mobile: The following mobile versions of Sleipnir for smartphones have been released: Android, iOS, Windows Phone

See also[edit]


  1. ^ "リリースノート (ie release note in Japanese)". Retrieved 2015-01-21. 
  2. ^ Sleipnir 3 Web Browser for Windows / Mac - Web browsing that links easily with smartphones
  3. ^ Corporate Symbol of Fenrir.
  4. ^ Translators wanted Sleipnir web browser Windows, Mac, Mobile (Fenrir Developer's Blog)
  5. ^ About language support for each product
  6. ^ (Japanese)「Sleipnir」「PictBear」の作者のパソコンが盗難に遭い開発中止に!?
  7. ^ (Japanese) フェンリル、タブブラウザ「Sleipnir」「Grani」のデフォルト検索エンジンをグーグルに:マーケティング - CNET Japan
  8. ^ BBC, Microsoft offers browser choices to Europeans, 1 March 2010
  9. ^ EU drops Microsoft browser charges with agreement on 'ballot screen' | Technology |
  10. ^ "Released Sleipnir 5 for Windows with the latest Blink engine". Sleipnir blog. December 24, 2013. Retrieved May 28, 2014. 
  11. ^ WebKit browsers for Windows - Sleipnir 3 joins the list with α3 (Fenrir Developer's Blog)
  12. ^ Mac App Store - Sleipnir Browser

External links[edit]