grok-4.1-fast

completions

byopenrouter

grok-4.1-fast

completions

Published by: xaiProvider:

openrouter

Grok 4.1 Fast is xAI's best agentic tool calling model that shines in real-world use cases like customer support and deep research. 2M context window. Reasoning can be enabled/disabled using the `reasoning` `enabled` parameter in the API. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#controlling-reasoning-tokens)

Released

Nov 17, 2025

Knowledge

May 21, 2025

License

Proprietary

Context

Input

$0.2 / 1M tokens

Output

$0.5 / 1M tokens

Cached

$0.05 / 1M tokens

Capabilities: tools, reasoning

Accepts: text, image

Returns: text

Released Nov 17, 2025Knowledge Cutoff: May 21, 2025License: Proprietary

Context: 2M Input: $0.2 / 1M tokensOutput: $0.5 / 1M tokensCached: $0.05 / 1M tokensCapabilities: tools, reasoningAccepts: text, imageReturns: text

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Benchmark Results for grok-4.1-fast

Category Performance Scores:

Maths: Score 89.30 (Top 15% - Rank #51)
Finance: Score 63.90 (Top 11% - Rank #38)
Science: Score 77.82 (Top 11% - Rank #38)
Writing: Score 66.08 (Top 17% - Rank #58)
Academia: Score 61.90 (Top 10% - Rank #34)
Marketing: Score 65.67 (Top 14% - Rank #48)
Programming: Score 30.90 (Top 21% - Rank #71)

Overall Performance: 65.08166666666666 average score across all categories

Detailed Benchmark Scores:

Benchmark	Score	Percentile	Domain
HLE	17.60	Top 15%	General Knowledge
GPQA	85.30	Top 7%	STEM (Physics, Chemistry, Biology)
SciCode	44.20	Top 7%	Scientific
MMLU-Pro	85.40	Top 11%	General Knowledge
LiveCodeBench	82.20	Top 11%	Programming
AA Math Index	89.30	Top 15%	Mathematics
AA Coding Index	30.90	Top 21%	Programming
AAII	38.50	Top 12%	General

GPQA Score: 85.30 - Graduate-level reasoning benchmark

Model Comparison:

Provider: openrouter

Model Type: completions

Context Size: 2000000 tokens

Comparing against 337 models in the database

Category Scores

Benchmark Tests

View Other Benchmarks

HLE

17.6

General Knowledge

GPQA

85.3

STEM (Physics, Chemistry, Biology)

SciCode

44.2

Scientific

MMLU-Pro

85.4

General Knowledge

LiveCodeBench

82.2

Programming

AA Math Index

89.3

Mathematics

AA Coding Index

30.9

Programming

AAII

38.5

General

Metric	HLE	GPQA	SciCode	MMLU-Pro	LiveCodeBench	AA Math Index	AA Coding Index	AAII
Score	17.6	85.3	44.2	85.4	82.2	89.3	30.9	38.5

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Code Examples

Integration samples and API usage

Code Samples for grok-4.1-fast

Python SDK Example:

from openai import OpenAI

client = OpenAI(
    base_url="https://api.us-east-1.langdb.ai/projects/<your_project_id>",
    api_key="<your_api_key>"
)

response = client.chat.completions.create(
    model="grok-4.1-fast",
    messages=[
        {"role": "user", "content": "Hello, how are you?"}
    ]
)

print(response.choices[0].message.content)

TypeScript SDK Example:

import OpenAI from 'openai';

const client = new OpenAI({
    baseURL: "https://api.us-east-1.langdb.ai/projects/<your_project_id>",
    apiKey: "<your_api_key>"
});

const response = await client.chat.completions.create({
    model: "grok-4.1-fast",
    messages: [
        { role: "user", content: "Hello, how are you?" }
    ]
});

console.log(response.choices[0].message.content);

cURL Example:

curl -X POST "https://api.us-east-1.langdb.ai/projects/<your_project_id>/v1/chat/completions" \
  -H "Authorization: Bearer <your_api_key>" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "grok-4.1-fast",
    "messages": [
        {"role": "user", "content": "Hello, how are you?"}
    ]
  }'

Model: grok-4.1-fast

Provider: openrouter

API Endpoint: $https://api.us-east-1.langdb.ai

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grok-4.1-fast by openrouter - AI Model Details, Pricing, and Performance Metrics

grok-4.1-fast

grok-4.1-fast

Access grok-4.1-fast through LangDB AI Gateway

Category Scores

Benchmark Tests

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