Grok 4 Fast (Reasoning): benchmark results

Grok 4 Fast evaluated with reasoning enabled. Provider: xAI. Released 2025-09-19. Access: API.

Unified ELO 1599 ± 1, rank #440 of 1761 rated models, from 154 benchmark results.

Strongest benchmark results

BenchmarkScoreMetricPercentile
NYT Connections Older Models88Score (%)96.8
LiveOIBench69.8Avg Human Percentile96.5
AA LiveCodeBench83.17Pass@1 (%)94.4
LLM2014 Logic 2025-0967.59Median Score93.3
UGI Leaderboard51.29UGI Score92.1
LLM2014 Logic 2025-1067.76Median Score91.8
Vals AI TaxEval v275.7Accuracy (%)91.7
Diplomacy: Overall Performance57.75Score90.9
AA AIME 202589.67Accuracy (%)90.7
AA MMLU-Pro85.04Accuracy (%)89.8
UGI - Writing53.37Writing Score89.8
UGI - Natural Intelligence46.53NatInt Score88.8

Interactive version: theaggregate.ai/model?slug=grok-4-fast-reasoning · How It Works · Data refreshed daily, snapshot 2026-09-05.