Grok 4 Fast
xAI🇺🇸 United States
Cost-efficient Grok 4 variant with a 2M-token context and unified reasoning/non-reasoning weights — Grok-4-level benchmark scores using ~40% fewer thinking tokens.
Context window2000K tokens
Input / 1M tokens$0.2
Output / 1M tokens$0.5
Version History
grok-4-fast-launchmajor
Grok 4 Fast launches. Cost-efficient Grok 4 variant with a 2M-token context and unified reasoning/non-reasoning weights — Grok-4-level benchmark scores using ~40% fewer thinking tokens.
Benchmark Scores
Full leaderboard →92.0%
AIME 2025
85.7%
GPQA
66.0%
Hallucination (Knowledge)
80.0%
LiveCodeBench