Fast, Lightweight HTML UI Engine
for Desktop Apps and Games
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Interfaces at the Speed of Light

Ultralight is a tool to display fast, beautiful HTML interfaces inside all kinds of applications.

Save time and money by writing your application's front-end with HTML while still retaining access to the power and performance of native C/C++ code.

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Ultralight is only a fraction of the size and memory usage of other solutions and supports most modern HTML5 and JavaScript features (built upon same core as WebKit/Safari).


Ultralight takes advantage of native hardware acceleration to offer best-in-class rendering performance across all platforms.


Ultralight supports most major desktop PC platforms. Specifically, Windows (7+, x64), macOS (Sierra or later), and Linux (Ubuntu/Debian 9.5+, x64).

We're currently porting Ultralight to Xbox One and PS4, with plans to port it to ARM64 and others soon after.

Ultralight supports most major websites out of the box!

There are few things still missing which you can track here.

We recommend trying out the Browser sample to get an idea of what Ultralight is capable of today.

Yep! Ultralight uses the same JavaScript engine as WebKit/Safari.


Ultralight can render to an offscreen bitmap for upload to a texture (see Sample 7 - OpenGL Integration) or— if you need extra performance— the engine can render directly to the GPU using low-level driver commands.

See our game integration guide for more info.

We maintain official API for C++ and C.

Several awesome members of our community maintain bindings for C#, Java, Rust, and Go on top of our portable C API.

The WebCore and AppCore modules are available open-source on GitHub.

The UltralightCore and Ultralight modules are proprietary— source code access to these repos can be obtained through a custom license.


Build your first app in 5 minutes— try the quick-start today!

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