Elon Musk's xAI company has launched a new addition to its product lineup — the Grok 4 Fast model. Currently, users can access this model through the model selector on the Grok web interface by enabling a newly added toggle switch under "Subscription Settings," which is labeled as "Early Access Beta."

Grok 4 Fast's main advantage lies in its speed. User feedback indicates that its response time can be up to 10 times faster than the standard Grok 4. The primary distinction between the two versions is that Grok 4 Fast has been specifically optimized to reduce processing time for complex tasks, thereby achieving faster responses. For instance, when given a command to generate an SVG image of a robot, the output will intentionally adopt a basic and simplified format, clearly reflecting the model's core principle of prioritizing speed over complexity.

This design approach is particularly beneficial for users seeking immediate results, as Grok 4 Fast's rapid response can significantly enhance efficiency. However, the model also shows notable limitations in certain scenarios — when faced with creative demands or tasks requiring detailed processing, it sacrifices depth and detail richness to maintain fast response times.

It's worth noting that Grok 4 Fast isn't making its debut here. Previously, the model was internally tested on the Arena platform under the codename "Sonoma," indicating that xAI had already conducted a period of low-key experimentation and optimization before its official release.

At present, Grok 4 Fast remains in the "Early Access" phase and may be made available to free users in the future, potentially even replacing the older Grok 3.

In addition, xAI has introduced a dedicated "Update Log" section on the Grok web interface to publicly share real-time updates about product iterations. It is also reported that Grok 4 Fast will be adapted for mobile applications in the future.