Models / grok-4-fast-reasoning
xAIgrok-4-fast-reasoning
12 published results from 3 sources. Each card shows where the number comes from and what it does not measure. Results are never combined into one score.
- Provider
- xAI
- Sources
- 3
- Our benchmarks
- 0
- Price
- Not yet published
Reported by others
1,417
Overall · rank 113 of 177
- Unit
- Arena rating, higher is better
- Range
- 1,411 to 1,423
- Sample
- 10597 votes
- Configuration
- grok-4-fast-reasoning
- Measured
- 25 Sep 2026
- Not shown
- Not an error rate: claims that cannot be checked on the web are skipped, and preference still carries most of the weight.
1,403
Business, management and finance · rank 117 of 402
- Unit
- Arena rating, higher is better
- Range
- 1,393 to 1,413
- Sample
- 3559 votes
- Configuration
- grok-4-fast-reasoning
- Measured
- 25 Sep 2026
- Not shown
- Not accuracy or correctness: it ranks which answer voters preferred, with answer length and formatting controlled for.
1,383
Creative writing · rank 95 of 407
- Unit
- Arena rating, higher is better
- Range
- 1,371 to 1,395
- Sample
- 2478 votes
- Configuration
- grok-4-fast-reasoning
- Measured
- 25 Sep 2026
- Not shown
- Not accuracy or correctness: it ranks which answer voters preferred, with answer length and formatting controlled for.
1,421
Expert prompts · rank 106 of 359
- Unit
- Arena rating, higher is better
- Range
- 1,402 to 1,441
- Sample
- 924 votes
- Configuration
- grok-4-fast-reasoning
- Measured
- 25 Sep 2026
- Not shown
- Not accuracy or correctness: it ranks which answer voters preferred, with answer length and formatting controlled for.
1,389
Instruction following · rank 131 of 409
- Unit
- Arena rating, higher is better
- Range
- 1,380 to 1,397
- Sample
- 5284 votes
- Configuration
- grok-4-fast-reasoning
- Measured
- 25 Sep 2026
- Not shown
- Not accuracy or correctness: it ranks which answer voters preferred, with answer length and formatting controlled for.
1,405
Overall · rank 134 of 409
- Unit
- Arena rating, higher is better
- Range
- 1,400 to 1,410
- Sample
- 18151 votes
- Configuration
- grok-4-fast-reasoning
- Measured
- 25 Sep 2026
- Not shown
- Not accuracy or correctness: it ranks which answer voters preferred, with answer length and formatting controlled for.
1,388
Writing, literature and language · rank 111 of 408
- Unit
- Arena rating, higher is better
- Range
- 1,379 to 1,397
- Sample
- 4133 votes
- Configuration
- grok-4-fast-reasoning
- Measured
- 25 Sep 2026
- Not shown
- Not accuracy or correctness: it ranks which answer voters preferred, with answer length and formatting controlled for.
23.0%
Requested-length error · rank 208 of 370
- Unit
- % off the requested word count, lower is better
- Configuration
- grok-4-fast-reasoning
- Measured
- 24 Sep 2025
- Not shown
- Not other format limits such as character counts or bullet counts.
0.33
Style adherence · rank 259 of 370
- Unit
- score from 0 to 1, higher is better
- Configuration
- grok-4-fast-reasoning
- Measured
- 24 Sep 2025
- Not shown
- Not brand voice on your own examples: UGI's prompts are private and lean towards creative writing.
53.4
Writing score · rank 139 of 370
- Unit
- score out of 100, higher is better
- Configuration
- grok-4-fast-reasoning
- Measured
- 24 Sep 2025
- Not shown
- Not business copy quality: UGI's prompts are private and lean towards creative writing, and models that often refuse get no score.
99.5%
Answer rate · rank 53 of 108
- Unit
- % of documents, higher is better
- Configuration
- grok-4-fast-reasoning
- Measured
- 22 Sep 2026
- Not shown
- Not a quality score: a low rate usually means content filters were triggered, and hallucination rates are measured on answered documents only.
20.2%
Hallucination rate · rank 103 of 108
- Unit
- % of summaries, lower is better
- Configuration
- grok-4-fast-reasoning
- Measured
- 22 Sep 2026
- Not shown
- Not errors in open questions or other tasks: only summarisation, judged by Vectara's own model (HHEM-2.3), not by people, on news-style documents rather than your data.
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