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xAI · Frontier

Grok 4.5

Added Jul 8, 2026

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Use in the app

Grok 4.5 is SpaceXAI's frontier reasoning model for coding, knowledge work, and STEM. It supports text, image, and file inputs with tool calling and structured outputs. Reasoning is always active. 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
Reasoning effort
low · medium · high
Discovery tier
Frontier

Pricing

USD per 1M tokens
Input
$2.00
Output
$6.00
Cache read
$0.30

Reference prices as published by the model provider. API example

Specifications

Context window
500K
Max output
—
Average output (7 days)
1K tokens
Longer than 71% of 473 models

Side by side

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TryMuse Spark OpenGemini 3.7 FlashGPT 5.5All 3

Public evaluations

Benchmarks

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

Intelligence Index

38.8

Tested at high reasoning effort

Better than 83% of 326 scored models

3.8Catalog models by score55.1

Indexes

  • Coding Index

    72.4

    Composite of the coding evaluations

    Better than 83% of 168 scored models

Agentic work

  • AutomationBench-AA

    57.9%

    Workflow automation, penalized for guardrail violations

    Better than 74% of 173 scored models

  • AutomationBench-AA tasks completed

    26.3%

    Workflows finished end to end without a guardrail violation

    Better than 79% of 173 scored models

  • AA-Briefcasev1.1

    1,278 Elo

    Agentic knowledge work, rated head to head

    Better than 66% of 166 scored models

  • GDPval-AAv2.1

    1,381 Elo

    Economically valuable occupational tasks, rated head to head

    Better than 63% of 187 scored models

Document reasoning

  • GDP.pdf

    18.8%

    Professional reasoning over PDF documents, all-pass rate

    Better than 73% of 171 scored models

  • AA-LCRv1.1

    79.3%

    Reasoning across long documents

    Better than 73% of 309 scored models

  • MLCR-AA

    16.1%

    Long-context reasoning over medical records

    Better than 68% of 121 scored models

Reasoning and knowledge

  • Humanity’s Last Exam

    42.7%

    Expert-level questions across academic fields

    Better than 84% of 323 scored models

  • GPQA Diamond

    93.1%

    Graduate-level science questions

    Better than 92% of 291 scored models

Coding

  • Terminal-Benchv4.0

    10.6%

    Practical software engineering in a terminal

    Better than 60% of 171 scored models

  • SciCode

    55.0%

    Scientific computing in Python

    Better than 74% of 174 scored models

Legacy evaluations

  • AA-LCR (unversioned)

    79.3%

    Long-context reasoning, earlier grading

    Better than 73% of 309 scored models

Scores from Artificial Analysis, updated Oct 26, 2026. Grok 4.5 was tested at high reasoning effort; compare scores measured at the same effort.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
54.1 tok/s
Faster than 36% of 257 models
Time to first token
2.5 s
Quicker than 65% of 257 models
Prompt cache hits
58.8%
About $1.00 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 66.6%
  • 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-4.5",
    "reasoning_effort": "medium",
    "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-4.5",
    messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)

xAI

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