grok-4-fastGrok 4 Fast is xAI’s proprietary AI model, released Sep 19, 2025.
Scores on standardized evaluations. Higher is better — and rank shows where Grok 4 Fast lands among all models tracked on Model Beat.
Abstract visual reasoning
Harder abstract reasoning
Graduate-level scientific reasoning
Frontier of human expert knowledge
Broad expert knowledge
Novel ML problem-solving
Contamination-free coding
Scientific research coding
Human-rated web development
Olympiad-qualifier math
Tool-agent-user reliability
Grok 4 Fast is a Grok-family AI model, from xAI, released Sep 19, 2025.
Grok 4 Fast is an AI model developed by xAI, part of the Grok family, released Sep 19, 2025.
On standardized evaluations tracked by Epoch AI, Grok 4 Fast scores 83.2% on LiveCodeBench, 85.0% on MMLU-Pro, 89.7% on AIME 2024/2025.
Grok 4 Fast is a proprietary model (API access), available through its provider's API rather than as a downloadable open-weight model.
Benchmark data from Epoch AI (CC BY) and Artificial Analysis; pricing, specs & descriptions from OpenRouter. Data updated Sep 4, 2026.