Sleipnir 6.5.12

Fenrir Inc. ❘ 33.6MB ❘ Freeware ❘
Windows

Sleipnir: The Versatile Browser for Enhanced Web Navigation

Boris Weber

06/14/2025

Sleipnir by Fenrir Inc. offers a unique and customizable browsing experience with features that cater to power users seeking advanced tab management and browser personalization.

Discover Sleipnir: A Powerful, Customizable Web Browser for Enhanced Browsing

Sleipnir, developed by Fenrir Inc., stands out as a versatile and innovative web browser designed to elevate your online experience. Named after the legendary Norse eight-legged horse, Sleipnir delivers speed, security, and extensive customization features in one package.

Advanced Tab Management for Increased Productivity

One of Sleipnir's key highlights is its unique tab management system. Users can organize their tabs in various layouts, including vertical and horizontal stacks, enabling seamless navigation and multitasking. This makes it ideal for power users juggling multiple websites simultaneously.

Highly Customizable Interface and Themes

Sleipnir offers unparalleled customization options. Personalize your browsing environment with a wide variety of themes, background images, and icons. Additionally, adjustable settings allow you to tailor the browser's appearance and behavior to suit your preferences.

Enhanced Security and Privacy Features

Built-in ad blocker
Tracking protection to guard against online threats
Support for extensions to add extra security tools

Fast, Efficient Performance with Unique Rendering Engine

Sleipnir is engineered for speed and efficiency, utilizing a proprietary rendering engine optimized for fast page loading and smooth browsing. This ensures a reliable, lag-free online experience.

Seamless Synchronization Across Devices

The browser supports synchronization of bookmarks, passwords, and browsing history across multiple devices. This feature is perfect for users who need a consistent browsing environment wherever they go.

Integrations with Popular Web Services

Sleipnir easily integrates with various web platforms, enhancing your workflow by allowing quick access to your favorite services directly from the browser.

Conclusion

Sleipnir by Fenrir Inc. combines speed, security, and customization in a robust browser tailored for demanding users. Its innovative tab management, high adaptability, and performance-centric design make it an excellent choice for those seeking a reliable alternative to mainstream browsers.

Overview

Sleipnir is a Freeware software in the category Internet developed by Fenrir Inc..

The users of our client application UpdateStar have checked Sleipnir for updates 126 times during the last month.

The latest version of Sleipnir is 6.5.12, released on 07/11/2025. It was initially added to our database on 10/29/2007. The most prevalent version is 6.5.12, which is used by 75% of all installations.

Sleipnir runs on the following operating systems: Windows. The download file has a size of 33.6MB.

Users of Sleipnir gave it a rating of 5 out of 5 stars.

Pros

Highly customizable browser with various themes and settings to personalize the browsing experience
Supports multiple browsing engines, allowing users to switch between Trident and Blink rendering engines
Integration with various popular services like Evernote and Facebook for seamless productivity
Offers unique features like tab grouping and thumbnail tabs for better organization
Sync capabilities across devices for bookmarks, history, and settings

Cons

Can be overwhelming for new users due to the extensive customization options
Some users may experience occasional compatibility issues with certain websites
Resource-heavy compared to other mainstream browsers, leading to potential performance issues on low-end hardware

FAQ

What is Sleipnir?

Sleipnir is a web browser developed by Fenrir Inc. It is known for its high level of customization and speed.

What operating systems does Sleipnir support?

Sleipnir is available for Windows, Mac, iOS, and Android.

What makes Sleipnir different from other browsers?

Sleipnir offers unique features such as tab groups, customizable gestures, and syncing across devices.

Is Sleipnir free to use?

Yes, Sleipnir is available to download and use for free.

Can extensions be installed on Sleipnir?

Yes, Sleipnir supports extensions to add additional functionality to the browser.

Is Sleipnir a secure browser?

Sleipnir includes features such as ad-blocking and anti-tracking to increase security and privacy.

Can bookmarks be imported from other browsers?

Yes, Sleipnir has the ability to import bookmarks from popular browsers such as Chrome and Firefox.

Does Sleipnir support multiple languages?

Yes, Sleipnir is available in multiple languages including English, Japanese, and Chinese.

Does Sleipnir have a mobile app?

Yes, Sleipnir is available as a mobile app for iOS and Android devices.

Can I create custom themes on Sleipnir?

Yes, Sleipnir allows users to create and customize their own themes using CSS.

Boris Weber

I am an editor at UpdateStar. I started as a support engineer, and am now specialized in writing about general software topics from a usability and performance angle among others. I telecommute from UpdateStar’s Berlin office, when I am not working remote as a digital nomad for UpdateStar. When I'm not analyzing the latest software updates, you can find me exploring new cities, immersing myself in local cultures, and discovering innovative tech trends across the globe.

Latest Reviews by Boris Weber

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Installations

126 users of UpdateStar had Sleipnir installed last month.

Latest Version
6.5.12

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