grok-4-fast

completions

byopenrouter

grok-4-fast

completions

Published by: x-aiProvider:

openrouter

Grok 4 Fast is xAI's latest multimodal model with SOTA cost-efficiency and a 2M token context window. It comes in two flavors: non-reasoning and reasoning. Read more about the model on xAI's [news post](http://x.ai/news/grok-4-fast). Reasoning can be enabled using the `reasoning` `enabled` parameter in the API. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#controlling-reasoning-tokens) Prompts and completions on Grok 4 Fast Free may be used by xAI or OpenRouter to improve future models.

Released

Aug 28, 2025

Knowledge

Mar 1, 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 Aug 28, 2025Knowledge Cutoff: Mar 1, 2025License: Proprietary

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

Access grok-4-fast through LangDB AI Gateway

Recommended

Integrate with x-ai's grok-4-fast and 250+ other models through a unified API. Monitor usage, control costs, and enhance security.

Unified API

Cost Optimization

Enterprise Security

Get Started Now

Free tier available • No credit card required

Instant Setup

99.9% Uptime

10,000+Monthly Requests

Benchmark Results for grok-4-fast

Category Performance Scores:

Academia: Score 62.15 (Top 20% - Rank #71)
Finance: Score 39.95 (Top 55% - Rank #195)
Marketing: Score 43.70 (Top 53% - Rank #188)
Maths: Score 41.30 (Top 52% - Rank #185)
Programming: Score 28.10 (Top 56% - Rank #199)
Science: Score 71.79 (Top 21% - Rank #75)
Writing: Score 46.03 (Top 46% - Rank #163)

Overall Performance: 47.575634920634926 average score across all categories

Detailed Benchmark Scores:

Benchmark	Score	Percentile	Domain
AA Coding Index	28.10	Top 56%	Programming
AAII	38.60	Top 38%	General
AA Math Index	41.30	Top 52%	Mathematics
GPQA	85.70	Top 2%	STEM (Physics, Chemistry, Biology)
HLE	5.00	Top 46%	General Knowledge
LiveCodeBench	40.10	Top 44%	Programming
MMLU-Pro	73.00	Top 64%	General Knowledge
SciCode	32.90	Top 43%	Scientific

GPQA Score: 85.70 - Graduate-level reasoning benchmark

Model Comparison:

Provider: openrouter

Model Type: completions

Context Size: 2000000 tokens

Comparing against 354 models in the database

Performance Analytics for grok-4-fast

Usage Statistics (Last 8 Days):

Total Requests: 400 API calls
Average TPS: 883.19 tokens per second
Average Response Time: 17505.40ms
Average Time to First Token: 15833.20ms
Total Cost: $1.90
Average Request Cost: $0.0048

Daily Performance Breakdown:

Date	Requests	TPS	Response Time	TTFT	Cost
11/11/2025	89	841.51	22532.30ms	22532.30ms	$0.53
11/12/2025	42	1219.96	21602.80ms	21066.40ms	$0.33
11/13/2025	58	659.37	14303.10ms	11425.90ms	$0.18
11/14/2025	24	1068.42	18805.20ms	17270.20ms	$0.15
11/15/2025	101	1054.02	9066.80ms	5797.30ms	$0.25
11/16/2025	35	814.21	22542.50ms	20689.50ms	$0.21
11/17/2025	48	702.12	21088.60ms	20097.70ms	$0.24
11/18/2025	3	461.28	30530.40ms	30530.40ms	$0.02

Performance Summary:

Model: grok-4-fast by openrouter

Monitoring Period: 11/11/2025 to 11/18/2025

Average Daily Requests: 50

Peak Daily Requests: 101

Statistics

View Full Statistics

Request Volume

Daily API requests

400

Performance (TPS)

Tokens per second

883.19 tokens/s

Category Scores

Benchmark Tests

View Other Benchmarks

AA Coding Index

28.1

Programming

AAII

38.6

General

AA Math Index

41.3

Mathematics

GPQA

85.7

STEM (Physics, Chemistry, Biology)

HLE

5.0

General Knowledge

LiveCodeBench

40.1

Programming

MMLU-Pro

73.0

General Knowledge

SciCode

32.9

Scientific

Metric	AA Coding Index	AAII	AA Math Index	GPQA	HLE	LiveCodeBench	MMLU-Pro	SciCode
Score	28.1	38.6	41.3	85.7	5.0	40.1	73.0	32.9

Compare with Similar Models

gemini-2.5-pro-preview

Code Examples

Integration samples and API usage

Code Samples for grok-4-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-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-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-fast",
    "messages": [
        {"role": "user", "content": "Hello, how are you?"}
    ]
  }'

Model: grok-4-fast

Provider: openrouter

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

Create API Key

Related Models

Similar models from openrouter

grok-4-fast

grok-4-fast

Access grok-4-fast through LangDB AI Gateway

Statistics

Category Scores

Benchmark Tests

Compare with Similar Models

Code Examples

Related Models

afm-4.5b

aion-1.0

aion-1.0-mini

aion-rp-llama-3.1-8b

coder-large

cogito-v2-preview-deepseek-671b

grok-4-fast by openrouter - AI Model Details, Pricing, and Performance Metrics

grok-4-fast

grok-4-fast

Access grok-4-fast through LangDB AI Gateway

Statistics

Category Scores

Benchmark Tests

Compare with Similar Models

Code Examples

Related Models

afm-4.5b

aion-1.0

aion-1.0-mini

aion-rp-llama-3.1-8b

coder-large

cogito-v2-preview-deepseek-671b