Comprehensive side-by-side LLM comparison
Both models show comparable benchmark performance. Grok 4 Fast offers 1.8M more tokens in context window than Grok-4. Grok 4 Fast is $17.30 cheaper per million tokens. Both models have their strengths depending on your specific coding needs.
xAI
Grok 4 Fast is a multimodal language model developed by xAI. It achieves strong performance with an average score of 73.0% across 7 benchmarks. It excels particularly in SimpleQA (95.0%), HMMT 2025 (93.3%), AIME 2025 (92.0%). With a 2.0M token context window, it can handle extensive documents and complex multi-turn conversations. The model is available through 1 API provider. As a multimodal model, it can process and understand text, images, and other input formats seamlessly. Released in 2025, it represents xAI's latest advancement in AI technology.
xAI
Grok 4 represents the fourth generation of xAI's language models, developed to continue advancing the frontier of AI reasoning and knowledge. Built to handle increasingly complex tasks with enhanced reliability, it demonstrates xAI's commitment to pushing AI capabilities forward.
1 month newer

Grok-4
xAI
2025-07-09

Grok 4 Fast
xAI
2025-08-28
Cost per million tokens (USD)

Grok 4 Fast

Grok-4
Context window and performance specifications
Average performance across 3 common benchmarks

Grok 4 Fast

Grok-4
Grok-4
2024-12-31
Available providers and their performance metrics

Grok 4 Fast
xAI

Grok-4

Grok 4 Fast

Grok-4

Grok 4 Fast

Grok-4
xAI
ZeroEval