"Elon Musk’s xAI has launched Grok 4 Fast, a powerful AI model with a massive 2M token context, blazing speed, and game-changing cost efficiency."
Elon Musk’s AI company xAI has just launched Grok 4 Fast, a large language model (LLM) designed to be faster, cheaper, and more powerful than most of today’s top AI models. Packed with a 2 million token context window and advanced reinforcement learning, Grok 4 Fast could change how businesses and developers use AI.
What makes Grok 4 Fast different?
Unlike earlier versions, Grok 4 Fast combines reasoning and non-reasoning tasks in one system. This reduces latency and cuts costs by about 40% compared to its predecessor. The model can handle very large documents, perform deep reasoning, and still deliver answers quickly.
- Context window: 2M tokens (ideal for large inputs)
- Efficiency: Uses fewer tokens for the same output
- Speed: 296–344 tokens per second
- Tool use: Built-in search, code execution, and real-time updates
How does Grok 4 Fast perform in benchmarks?
Independent tests show Grok 4 Fast competes directly with Google’s Gemini 2.5 Pro and Anthropic’s Claude 4.1 Opus. What makes it impressive is efficiency it needed only 61M tokens to complete the Artificial Analysis Intelligence Index compared to Gemini’s 93M and Grok 4’s 120M.
| Model | Tokens Used | Speed (tokens/sec) |
|---|---|---|
| Grok 4 Fast | 61M | 296–344 |
| Gemini 2.5 Pro | 93M | ~250 |
| Grok 4 | 120M | ~200 |
Why is pricing a big deal?
xAI is making Grok 4 Fast highly affordable compared to rivals. Businesses can get enterprise-grade reasoning without breaking the bank.
- Input tokens: $0.20/million (up to 128k) | $0.40/million (above 128k)
- Output tokens: $0.50/million (below 128k) | $1.00/million (above 128k)
- Cached input tokens: $0.05/million
Compared to Gemini 2.5 Pro, Grok 4 Fast can cut operational costs by up to 98%.
Who should use Grok 4 Fast?
It’s ideal for companies and developers who need speed and cost savings. Some common use cases include:
- Large-scale report generation
- Technical and academic research
- Intelligent search and RAG systems
- Content moderation and automation
- Code execution and validation
How to access Grok 4 Fast?
For now, Grok 4 Fast is free to try on xAI’s platform and via third-party providers. You can test it on:
FAQs about Grok 4 Fast
1. What is the context window size of Grok 4 Fast?
It supports up to 2 million tokens, one of the largest in the industry.
2. Is Grok 4 Fast better than GPT-5?
In speed tests, Grok 4 Fast outperformed GPT-5 in real-time scenarios, though both are strong in reasoning.
3. How much does it cost to use?
Pricing starts at just $0.20 per million input tokens, making it one of the cheapest enterprise-ready models.
