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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

Grok 4.3 compared

Specifications, prices, speed and benchmark scores next to each other. Benchmarks below show every compared model too.

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Grok 4.3xAIThis modelDeepSeek V3.1 TerminusDeepSeekRemove
ProviderxAIDeepSeek
Discovery tierBalancedOpen weights
AddedApr 30, 2026Aug 2, 2025
Limits
Context window1MBest128K
Max output—65.54K
Average output466 tokens364 tokens
Pricing, USD per 1M tokens
Input$1.25$0.25Best
Output$2.50$0.70Best
Cache read$0.20—
Performance
Throughput357.8 tok/sBest21.3 tok/s
Time to first token17.5 s3.7 sBest
Request success (24h)100.0%100.0%
Benchmark indexes
Intelligence Index14.0Best13.9
Coding Index35.2—
Math Index—53.7
Capabilities
ReasoningYesNo
ToolsYesYes
VisionYesNo
Structured outputYesYes
Reasoning effort——

Public evaluations

Benchmarks

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

  • Grok 4.3
  • DeepSeek V3.1 Terminus

Intelligence Index

  • Grok 4.314.0
  • DeepSeek V3.1 Terminus13.9

Grok 4.3: Better than 35% of 326 scored models

3.8Catalog models by score55.1

Indexes

  • Coding Index

    Composite of the coding evaluations

    • Grok 4.3: 35.2
    • DeepSeek V3.1 Terminus: —
  • Math Index

    Composite of the math evaluations

    • Grok 4.3: —
    • DeepSeek V3.1 Terminus: 53.7

Agentic work

  • AutomationBench-AA

    Workflow automation, penalized for guardrail violations

    • Grok 4.3: 0.9%
    • DeepSeek V3.1 Terminus: —
  • AutomationBench-AA tasks completed

    Workflows finished end to end without a guardrail violation

    • Grok 4.3: 0.2%
    • DeepSeek V3.1 Terminus: —
  • AA-Briefcasev1.1

    Agentic knowledge work, rated head to head

    • Grok 4.3: 724 Elo
    • DeepSeek V3.1 Terminus: —
  • GDPval-AAv2.1

    Economically valuable occupational tasks, rated head to head

    • Grok 4.3: 941 Elo
    • DeepSeek V3.1 Terminus: —

Document reasoning

  • GDP.pdf

    Professional reasoning over PDF documents, all-pass rate

    • Grok 4.3: 2.8%
    • DeepSeek V3.1 Terminus: —
  • AA-LCRv1.1

    Reasoning across long documents

    • Grok 4.3: 32.3%
    • DeepSeek V3.1 Terminus: 45.3%Top
  • MLCR-AA

    Long-context reasoning over medical records

    • Grok 4.3: 5.6%
    • DeepSeek V3.1 Terminus: —

Reasoning and knowledge

  • Humanity’s Last Exam

    Expert-level questions across academic fields

    • Grok 4.3: 6.8%
    • DeepSeek V3.1 Terminus: 8.7%Top
  • GPQA Diamond

    Graduate-level science questions

    • Grok 4.3: 65.8%
    • DeepSeek V3.1 Terminus: 75.1%Top
  • MMLU-Pro

    Multi-subject knowledge and reasoning

    • Grok 4.3: —
    • DeepSeek V3.1 Terminus: 83.6%
  • IFBench

    Following precise output instructions

    • Grok 4.3: 47.6%Top
    • DeepSeek V3.1 Terminus: 41.2%

Coding

  • Terminal-Benchv4.0

    Practical software engineering in a terminal

    • Grok 4.3: 0.0%
    • DeepSeek V3.1 Terminus: —
  • SciCode

    Scientific computing in Python

    • Grok 4.3: 39.4%
    • DeepSeek V3.1 Terminus: —
  • LiveCodeBench

    Recent competitive programming problems

    • Grok 4.3: —
    • DeepSeek V3.1 Terminus: 52.9%

Math

  • AIME 2025

    Competition mathematics, 2025 problems

    • Grok 4.3: —
    • DeepSeek V3.1 Terminus: 53.7%

Legacy evaluations

  • Terminal-Bench Hard

    Earlier terminal task suite

    • Grok 4.3: 18.9%
    • DeepSeek V3.1 Terminus: 31.8%Top
  • τ²-Bench Telecom

    Tool use in a customer-support simulation

    • Grok 4.3: 65.8%Top
    • DeepSeek V3.1 Terminus: 37.1%
  • AA-LCR (unversioned)

    Long-context reasoning, earlier grading

    • Grok 4.3: 32.3%
    • DeepSeek V3.1 Terminus: 45.3%Top

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.

Throughput
357.8 tok/s
Faster than 95% of 260 models
Time to first token
17.5 s
Quicker than 4% of 260 models
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)

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