xAI, proprietary

# Grok 4 Fast

> Grok 4 Fast by xAI, released September 2025. Ranked #167 of 354 with a Noometry Index of 39.4. Scores, sources and comparisons.
- Canonical page: https://noometry.com/models/grok-4-fast
- Last updated: 2026-10-10
- Title: Grok 4 Fast Benchmarks, Price & Rank (October 2026)

Grok 4 Fast by xAI ranks 167th of 354 ranked models on the Noometry Index as of October 2026, with a score of 39.4. Its strongest category is long context, where it ranks 3rd.

Last verified October 10, 2026

## Specifications

- **Noometry rank:** #167 of 354
- **Index score:** 39.4
- **Evidence:** Confirmed 30 results
- **Provider:** [xAI](https://noometry.com/providers/xai)
- **Released:** September 19, 2025
- **Weights:** Proprietary
- **Reasoning:** Unknown
- **Context window:** —
- **Max output:** —
- **Input price:** Not listed
- **Output price:** Not listed
- **Blended price:** Not listed
- **Output speed:** 577 tokens/s [Kagi](https://help.kagi.com/kagi/ai/llm-benchmark.html)
- **Value:** Not ranked
- **Knowledge cutoff:** Unknown

## Category scores

Each category score combines every public result we have in that category.

Grok 4 Fast category scores

1.  Coding 32.5
2.  Agentic & Tool Use 29.5
3.  Reasoning 22.2
4.  Math 38.9
5.  Knowledge 32.0
6.  Multilingual 51.3
7.  Instruction Following 73.2
8.  Long Context 63.2
9.  Writing & Preference 60.0
10.  020406080

Grok 4 Fast category ranks
| Category | Score | Rank | Results |
| --- | --- | --- | --- |
| [Coding](https://noometry.com/best/coding) | 32.5 | #271 | 3 |
| [Agentic & Tool Use](https://noometry.com/best/agentic) | 29.5 | #86 | 2 |
| [Reasoning](https://noometry.com/best/reasoning) | 22.2 | #201 | 5 |
| [Math](https://noometry.com/best/math) | 38.9 | #123 | 1 |
| [Knowledge](https://noometry.com/best/knowledge) | 32.0 | #214 | 2 |
| [Multilingual](https://noometry.com/best/multilingual) | 51.3 | #111 | 1 |
| [Instruction Following](https://noometry.com/best/instruction-following) | 73.2 | #121 | 1 |
| [Long Context](https://noometry.com/best/long-context) | 63.2 | #3 | 2 |
| [Writing & Preference](https://noometry.com/best/writing) | 60.0 | #102 | 3 |

## Strengths and weaknesses

Categories where Grok 4 Fast places highest and lowest among the models ranked in each, with its score against that category's median.

### Strongest categories

Grok 4 Fast: strongest categories
| Category | Score | vs median | Rank |
| --- | --- | --- | --- |
| [Long Context](https://noometry.com/best/long-context) | 63.2 | +22.3 | #3 of 296, top 2% |
| [Writing & Preference](https://noometry.com/best/writing) | 60.0 | +6.2 | #102 of 312, top 33% |
| [Multilingual](https://noometry.com/best/multilingual) | 51.3 | +3.9 | #111 of 297, top 38% |

### Weakest categories

Grok 4 Fast: weakest categories
| Category | Score | vs median | Rank |
| --- | --- | --- | --- |
| [Coding](https://noometry.com/best/coding) | 32.5 | −6.3 | #271 of 340, top 80% |
| [Knowledge](https://noometry.com/best/knowledge) | 32.0 | −5.3 | #214 of 314, top 69% |
| [Reasoning](https://noometry.com/best/reasoning) | 22.2 | −1.4 | #201 of 350, top 58% |

## Closest competitors

The models ranked just above and below Grok 4 Fast. When scores are this close, price and speed are often the better way to choose.

Models ranked closest to Grok 4 Fast
| Model | Rank | Score | Blended $/M | Speed |  |
| --- | --- | --- | --- | --- | --- |
| [Hunyuan Turbo 0110](https://noometry.com/models/hunyuan-turbo) | #163 | 39.6 | — | — | [Compare](https://noometry.com/compare/grok-4-fast-vs-hunyuan-turbo) |
| [Claude 3.7 Sonnet](https://noometry.com/models/claude-3-7-sonnet) | #164 | 39.5 | — | — | [Compare](https://noometry.com/compare/claude-3-7-sonnet-vs-grok-4-fast) |
| [Claude Haiku 4.5](https://noometry.com/models/claude-haiku-4-5) | #165 | 39.5 | $2 | — | [Compare](https://noometry.com/compare/claude-haiku-4-5-vs-grok-4-fast) |
| [DeepSeek-V3](https://noometry.com/models/deepseek-v3) | #166 | 39.5 | $0.41 | 73 | [Compare](https://noometry.com/compare/deepseek-v3-vs-grok-4-fast) |
| [Olmo 3.1 32b Instruct](https://noometry.com/models/olmo-3-1-32b-instruct) | #168 | 39.4 | — | — | [Compare](https://noometry.com/compare/grok-4-fast-vs-olmo-3-1-32b-instruct) |
| [Granite 4.2 3b](https://noometry.com/models/granite-4-2-3b) | #169 | 39.4 | — | — | [Compare](https://noometry.com/compare/granite-4-2-3b-vs-grok-4-fast) |
| [Gemini 2.5 Flash](https://noometry.com/models/gemini-2-5-flash) | #170 | 39.3 | $0.85 | 152 | [Compare](https://noometry.com/compare/gemini-2-5-flash-vs-grok-4-fast) |
| [Step 2 16k Exp 202412](https://noometry.com/models/step-2-16k-exp-202412) | #171 | 39.2 | — | — | [Compare](https://noometry.com/compare/grok-4-fast-vs-step-2-16k-exp-202412) |

Sponsored placements are available on pages like this one. [Advertise on Noometry](https://noometry.com/advertise)

## Benchmark results

Every published result we track, with its source. Bold rows are the ones used for ranking; where several exist we prefer independent runs over self-reported numbers.

### Coding

Grok 4 Fast Coding benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [LMArena WebDev](https://noometry.com/benchmarks/arena-webdev) | 1159 | #112 of 113, top 100% |  | [LMArena](https://lmarena.ai/leaderboard/webdev) | 2026-10-08 |
| [WeirdML](https://noometry.com/benchmarks/weirdml) | 42.9% | #67 of 119, top 57% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |
| [LMArena Coding](https://noometry.com/benchmarks/arena-coding) | 1429 | #111 of 294, top 38% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Coding](https://noometry.com/benchmarks/arena-coding) | 1420 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |

### Agentic & Tool Use

Grok 4 Fast Agentic & Tool Use benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [τ²-bench Banking](https://noometry.com/benchmarks/tau2-banking) | 15.7% | #22 of 26, top 85% | high | [τ²-bench](https://taubench.com/) | 2026-05-05 |
| [Cybench](https://noometry.com/benchmarks/cybench) | 30% | #9 of 21, top 43% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |
| [LMArena Search](https://noometry.com/benchmarks/arena-search) | 1171 | #21 of 32, top 66% |  | [LMArena](https://lmarena.ai/leaderboard/search) | 2026-08-24 |

### Reasoning

Grok 4 Fast Reasoning benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [ARC-AGI-2](https://noometry.com/benchmarks/arc-agi-2) | 5.3% | #55 of 83, top 67% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |
| [Kagi LLM Benchmark](https://noometry.com/benchmarks/kagi-reasoning) | 66.1% | #32 of 99, top 33% |  | [Kagi LLM Benchmark](https://help.kagi.com/kagi/ai/llm-benchmark.html) |  |
| [Kagi LLM Benchmark](https://noometry.com/benchmarks/kagi-reasoning) | 35.4% |  |  | [Kagi LLM Benchmark](https://help.kagi.com/kagi/ai/llm-benchmark.html) |  |
| [ARC-AGI-1](https://noometry.com/benchmarks/arc-agi-1) | 48.5% | #57 of 83, top 69% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |
| [LMArena Hard Prompts](https://noometry.com/benchmarks/arena-hard-prompts) | 1405 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Hard Prompts](https://noometry.com/benchmarks/arena-hard-prompts) | 1412 | #115 of 297, top 39% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [DTBench](https://noometry.com/benchmarks/dtbench) | 82.7% | #63 of 151, top 42% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |
| [Epoch Capabilities Index](https://noometry.com/benchmarks/epoch-capabilities-index) | 144.2 | #86 of 213, top 41% |  | [Epoch AI](https://epoch.ai/eci) | 2025-09-19 |
| [ForecastBench](https://noometry.com/benchmarks/forecastbench) | 60.5 | #26 of 72, top 37% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |

### Math

Grok 4 Fast Math benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [LMArena Math](https://noometry.com/benchmarks/arena-math) | 1403 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Math](https://noometry.com/benchmarks/arena-math) | 1419 | #103 of 285, top 37% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |

### Knowledge

Grok 4 Fast Knowledge benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [Vectara Hallucination Rate](https://noometry.com/benchmarks/vectara-hallucination) (lower is better) | 20.2% |  |  | [Vectara Hallucination Leaderboard](https://github.com/vectara/hallucination-leaderboard) |  |
| [Vectara Hallucination Rate](https://noometry.com/benchmarks/vectara-hallucination) (lower is better) | 19.7% | #92 of 96, top 96% |  | [Vectara Hallucination Leaderboard](https://github.com/vectara/hallucination-leaderboard) |  |
| [LMArena Expert](https://noometry.com/benchmarks/arena-expert) | 1399 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Expert](https://noometry.com/benchmarks/arena-expert) | 1411 | #112 of 273, top 42% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |

### Multilingual

Grok 4 Fast Multilingual benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [LMArena Non-English](https://noometry.com/benchmarks/arena-non-english) | 1396 | #111 of 297, top 38% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Non-English](https://noometry.com/benchmarks/arena-non-english) | 1389 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Chinese](https://noometry.com/benchmarks/arena-chinese) | 1457 | #94 of 285, top 33% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Chinese](https://noometry.com/benchmarks/arena-chinese) | 1436 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena French](https://noometry.com/benchmarks/arena-french) | 1431 | #90 of 223, top 41% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena German](https://noometry.com/benchmarks/arena-german) | 1383 | #108 of 231, top 47% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Japanese](https://noometry.com/benchmarks/arena-japanese) | 1352 | #95 of 211, top 46% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Korean](https://noometry.com/benchmarks/arena-korean) | 1332 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Korean](https://noometry.com/benchmarks/arena-korean) | 1357 | #99 of 213, top 47% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Russian](https://noometry.com/benchmarks/arena-russian) | 1389 | #120 of 283, top 43% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Russian](https://noometry.com/benchmarks/arena-russian) | 1384 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Spanish](https://noometry.com/benchmarks/arena-spanish) | 1415 | #98 of 226, top 44% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Spanish](https://noometry.com/benchmarks/arena-spanish) | 1404 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |

### Instruction Following

Grok 4 Fast Instruction Following benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [LMArena Instruction Following](https://noometry.com/benchmarks/arena-instruction-following) | 1387 | #115 of 298, top 39% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Instruction Following](https://noometry.com/benchmarks/arena-instruction-following) | 1383 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |

### Long Context

Grok 4 Fast Long Context benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [Fiction.LiveBench](https://noometry.com/benchmarks/fiction-livebench) | 94.4% | #4 of 47, top 9% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |
| [LMArena Longer Query](https://noometry.com/benchmarks/arena-longer-query) | 1415 | #99 of 291, top 35% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Longer Query](https://noometry.com/benchmarks/arena-longer-query) | 1412 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |

### Writing & Preference

Grok 4 Fast Writing & Preference benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [LMArena Text](https://noometry.com/benchmarks/arena-text) | 1407 | #113 of 297, top 39% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Text](https://noometry.com/benchmarks/arena-text) | 1400 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Creative Writing](https://noometry.com/benchmarks/arena-creative-writing) | 1378 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Creative Writing](https://noometry.com/benchmarks/arena-creative-writing) | 1387 | #98 of 295, top 34% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Multi-Turn](https://noometry.com/benchmarks/arena-multi-turn) | 1414 | #104 of 295, top 36% |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |
| [LMArena Multi-Turn](https://noometry.com/benchmarks/arena-multi-turn) | 1404 |  |  | [LMArena](https://lmarena.ai/leaderboard/text) | 2026-10-08 |

## Compare Grok 4 Fast

-   [Grok 4 Fast vs Grok 4.1 Fast](https://noometry.com/compare/grok-4-1-fast-vs-grok-4-fast)
-   [Grok 4 Fast vs DeepSeek-V3](https://noometry.com/compare/deepseek-v3-vs-grok-4-fast)
-   [Grok 4 Fast vs Olmo 3.1 32b Instruct](https://noometry.com/compare/grok-4-fast-vs-olmo-3-1-32b-instruct)
-   [Grok 4 Fast vs Claude Haiku 4.5](https://noometry.com/compare/claude-haiku-4-5-vs-grok-4-fast)
-   [Grok 4 Fast vs Granite 4.2 3b](https://noometry.com/compare/granite-4-2-3b-vs-grok-4-fast)
-   [Grok 4 Fast vs Claude 3.7 Sonnet](https://noometry.com/compare/claude-3-7-sonnet-vs-grok-4-fast)
-   [Grok 4 Fast vs Gemini 2.5 Flash](https://noometry.com/compare/gemini-2-5-flash-vs-grok-4-fast)
-   [Grok 4 Fast vs GPT-6 Astra](https://noometry.com/compare/gpt-6-astra-vs-grok-4-fast)
-   [Grok 4 Fast vs Claude Fable 5.1](https://noometry.com/compare/claude-fable-5-1-vs-grok-4-fast)
-   [Grok 4 Fast vs Gemini 3.8 Flash](https://noometry.com/compare/gemini-3-8-flash-vs-grok-4-fast)
-   [Grok 4 Fast vs Kimi K3](https://noometry.com/compare/grok-4-fast-vs-kimi-k3)
-   [Grok 4 Fast vs Qwen3.8 Max](https://noometry.com/compare/grok-4-fast-vs-qwen3-8-max)
-   [Grok 4 Fast vs GLM-5.3](https://noometry.com/compare/glm-5-3-vs-grok-4-fast)
-   [Grok 4 Fast vs Muse Spark 1.3](https://noometry.com/compare/grok-4-fast-vs-muse-spark-1-3)

## Other xAI models

-   [Grok 4.6](https://noometry.com/models/grok-4-6)56.9
-   [Grok 4.5](https://noometry.com/models/grok-4-5)55.0
-   [Grok 4.7](https://noometry.com/models/grok-4-7)53.1
-   [Grok 4.20 (Non-Reasoning)](https://noometry.com/models/grok-4-20)48.6
-   [Grok 4](https://noometry.com/models/grok-4)48.1
-   [Grok 4.20 Multi-Agent](https://noometry.com/models/grok-4-20-multi-agent)46.2
-   [Grok 4.3](https://noometry.com/models/grok-4-3)43.8
-   [Grok 4.1](https://noometry.com/models/grok-4-1)41.5

## Frequently asked questions

### How good is Grok 4 Fast?

Grok 4 Fast by xAI ranks 167th of 354 ranked models on the Noometry Index as of October 2026, with a score of 39.4. Its strongest category is long context, where it ranks 3rd.

### Is Grok 4 Fast open source?

No. Grok 4 Fast is proprietary and available only through xAI's API and partner platforms.

### How fast is Grok 4 Fast?

Grok 4 Fast generated about 577 output tokens per second in the Kagi LLM Benchmark's timed runs. Speed varies by provider, load and reasoning effort.

### What are Grok 4 Fast's strengths and weaknesses?

Relative to other ranked models, Grok 4 Fast places best in long context, writing & preference, multilingual and lowest in coding, knowledge, reasoning.

### What is Grok 4 Fast best at?

Its best category is long context, where it ranks 3rd on Noometry.

### Cite this page

Noometry. (2026). Grok 4 Fast benchmarks and pricing. Retrieved October 10, 2026, from https://noometry.com/models/grok-4-fast

Quote Noometry with a link back to this page. It is also available in [Markdown](https://noometry.com/md/models/grok-4-fast.md).