Comprehensive side-by-side LLM comparison
Grok 4.1 Fast offers 1.0M more tokens in context window than Grok 3. Grok 4.1 Fast is $12.00 cheaper per million tokens. Both models have their strengths depending on your specific coding needs.
xAI
Grok 3, released by xAI in February 2025, is a large language model trained on xAI's Colossus supercluster with substantially increased compute over previous generations. It features a 1M token context window, RL-enhanced Think mode for extended reasoning, and demonstrated strong results on mathematics, coding, and scientific benchmarks. Grok 3 targets complex reasoning, real-time information tasks via X platform integration, 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.
9 months newer

Grok 3
xAI
2025-02-17

Grok 4.1 Fast
xAI
2025-11-17
Cost per million tokens (USD)
Grok 3
Grok 4.1 Fast
Context window and performance specifications
Available providers and their performance metrics
Grok 3
xAI
Grok 4.1 Fast
Grok 3
Grok 4.1 Fast
Grok 3
Grok 4.1 Fast
xAI