Comprehensive side-by-side LLM comparison
Grok 4.1 Fast offers 1.7M more tokens in context window than Grok 4. Grok 4.1 Fast is $24.00 cheaper per million tokens. Both models have their strengths depending on your specific coding needs.
xAI
Grok 4, released by xAI on July 10, 2025, is a large language model featuring first-principles reasoning and comprehensive multimodal support. It features a 260K token context window and demonstrated strong performance on advanced reasoning and coding benchmarks. Grok 4 targets complex multi-step reasoning tasks, scientific analysis, and agentic workflows via the xAI API.
xAI
Grok 4.1 Fast, released by xAI in November 2025, is a fast-response variant from the Grok 4 family featuring a 2M token context window designed for high-throughput applications. It omits thinking tokens for immediate responses, reducing latency while maintaining strong output quality. Grok 4.1 Fast targets production APIs, real-time assistants, and cost-sensitive applications requiring long-context understanding at high volume.
4 months newer

Grok 4
xAI
2025-07-10

Grok 4.1 Fast
xAI
2025-11-17
Cost per million tokens (USD)
Grok 4
Grok 4.1 Fast
Context window and performance specifications
Available providers and their performance metrics
Grok 4
xAI
Grok 4.1 Fast
Grok 4
Grok 4.1 Fast
Grok 4
Grok 4.1 Fast
xAI