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xAI · Balanced

Grok 4.3

Added Apr 30, 2026

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Use in the app

Grok 4.3 is SpaceXAI's reasoning model for text and image inputs, built for agentic workflows, instruction following, factual accuracy, long-document analysis, and deep research. Reasoning is always active and requests above 200k total tokens are charged at the higher long-context rate. Content policy rejections can still be charged: SpaceXAI may pass through a $0.05 moderation-failure fee, or a $0.055 usage-guidelines violation fee, depending on which rejection upstream returns.

  • Reasoning
  • Tools
  • Vision
  • Structured output
Input
Text, Images
Output
Text
Discovery tier
Balanced

Pricing

USD per 1M tokens
Input
$1.25
Output
$2.50
Cache read
$0.20

Reference prices as published by the model provider. API example

Specifications

Context window
1M
Max output
—
Average output (7 days)
466 tokens
Longer than 46% of 473 models

Side by side

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TryDeepSeek V3.1 TerminusGemma 4 31B IT TEEQwen3.5 9BAll 3

Public evaluations

Benchmarks

Independent evaluation results, with how each score ranks among the models in the Noumen catalog.

Intelligence Index

14.0

Better than 35% of 326 scored models

3.8Catalog models by score55.1

Indexes

  • Coding Index

    35.2

    Composite of the coding evaluations

    Better than 29% of 168 scored models

Agentic work

  • AutomationBench-AA

    0.9%

    Workflow automation, penalized for guardrail violations

    Better than 9% of 173 scored models

  • AutomationBench-AA tasks completed

    0.2%

    Workflows finished end to end without a guardrail violation

    Better than 13% of 173 scored models

  • AA-Briefcasev1.1

    724 Elo

    Agentic knowledge work, rated head to head

    Better than 25% of 166 scored models

  • GDPval-AAv2.1

    941 Elo

    Economically valuable occupational tasks, rated head to head

    Better than 31% of 187 scored models

Document reasoning

  • GDP.pdf

    2.8%

    Professional reasoning over PDF documents, all-pass rate

    Better than 12% of 171 scored models

  • AA-LCRv1.1

    32.3%

    Reasoning across long documents

    Better than 14% of 309 scored models

  • MLCR-AA

    5.6%

    Long-context reasoning over medical records

    Better than 18% of 121 scored models

Reasoning and knowledge

  • Humanity’s Last Exam

    6.8%

    Expert-level questions across academic fields

    Better than 24% of 323 scored models

  • GPQA Diamond

    65.8%

    Graduate-level science questions

    Better than 23% of 291 scored models

  • IFBench

    47.6%

    Following precise output instructions

    Better than 44% of 215 scored models

Coding

  • Terminal-Benchv4.0

    0.0%

    Practical software engineering in a terminal

    Better than 0% of 171 scored models

  • SciCode

    39.4%

    Scientific computing in Python

    Better than 20% of 174 scored models

Legacy evaluations

  • Terminal-Bench Hard

    18.9%

    Earlier terminal task suite

    Better than 37% of 212 scored models

  • τ²-Bench Telecom

    65.8%

    Tool use in a customer-support simulation

    Better than 50% of 214 scored models

  • AA-LCR (unversioned)

    32.3%

    Long-context reasoning, earlier grading

    Better than 14% of 309 scored models

Scores from Artificial Analysis, updated Oct 26, 2026. Artificial Analysis

Live routing data

Performance and reliability

Recent averages across requests routed for this model. Your own speed depends on prompt length, reasoning effort and load.

Prompt cache hits
19.9%
About $1.04 per 1M input tokens with caching
Request success (24h)
100.0%
Reliable

Cache hits are the share of input tokens recently served from a prompt cache across all requests. They are not a forecast of your own hit rate.

Hourly request success · last 72 hoursLowest hour 100.0%
  • Healthy (98% or more)
  • Degraded (90–98%)
  • Down (under 90%)
  • No requests

Developers

Use it through the API

Noumen’s API is OpenAI-compatible: any Chat Completions client works with a base URL and a key.

Read the quickstart
curl https://www.noumen.xyz/api/v1/chat/completions \
  -H "Authorization: Bearer $NOUMEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "x-ai/grok-4.3",
    "messages": [{ "role": "user", "content": "Explain this stack trace." }]
  }'
import os
from openai import OpenAI

client = OpenAI(base_url="https://www.noumen.xyz/api/v1", api_key=os.environ["NOUMEN_API_KEY"])
reply = client.chat.completions.create(
    model="x-ai/grok-4.3",
    messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)

xAI

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