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OpenAI · Frontier

GPT 5.2

Added Dec 11, 2025

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Use in the app

GPT-5.2 is an OpenAI GPT-5-series model with strong reasoning and long-context performance.

  • Reasoning
  • Tools
  • Vision
  • Structured output
  • PDF input
Input
Text, Images
Output
Text
Reasoning effort
none · low · medium · high · xhigh
Discovery tier
Frontier

Pricing

USD per 1M tokens
Input
$1.75
Output
$14.00
Cache read
$0.18

Reference prices as published by the model provider. API example

Specifications

Context window
400K
Max output
128K
Average output (7 days)
172 tokens
Longer than 17% of 465 models

Side by side

GPT 5.2 compared

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

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GPT 5.2OpenAIThis modelStep 3.5 Flash 2603stepfunRemove
ProviderOpenAIstepfun
Discovery tierFrontierOpen weights
AddedDec 11, 2025Apr 14, 2026
Limits
Context window400KBest262.14K
Max output128KBest65.54K
Average output172 tokens3K tokens
Pricing, USD per 1M tokens
Input$1.75$0.10Best
Output$14.00$0.30Best
Cache read$0.18—
Performance
Request success (24h)100.0%100.0%
Benchmark indexes
Intelligence Index17.017.0
Math Index51.0—
Capabilities
ReasoningYesYes
ToolsYesNo
VisionYesNo
Structured outputYesNo
PDF inputYesNo
Reasoning effortnone, low, medium, high, xhigh—

Public evaluations

Benchmarks

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

  • GPT 5.2
  • Step 3.5 Flash 2603

Intelligence Index

  • GPT 5.217.0
  • Step 3.5 Flash 260317.0

GPT 5.2: Better than 45% of 326 scored models

3.8Catalog models by score55.1

Indexes

  • Math Index

    Composite of the math evaluations

    • GPT 5.2: 51.0
    • Step 3.5 Flash 2603: —

Document reasoning

  • AA-LCRv1.1

    Reasoning across long documents

    • GPT 5.2: 45.7%
    • Step 3.5 Flash 2603: 63.0%Top

Reasoning and knowledge

  • Humanity’s Last Exam

    Expert-level questions across academic fields

    • GPT 5.2: 8.0%
    • Step 3.5 Flash 2603: 24.5%Top

  • GPQA Diamond

    Graduate-level science questions

    • GPT 5.2: 71.2%
    • Step 3.5 Flash 2603: 82.6%Top

  • MMLU-Pro

    Multi-subject knowledge and reasoning

    • GPT 5.2: 81.4%
    • Step 3.5 Flash 2603: —

  • IFBench

    Following precise output instructions

    • GPT 5.2: 47.4%
    • Step 3.5 Flash 2603: 66.5%Top

Coding

  • LiveCodeBench

    Recent competitive programming problems

    • GPT 5.2: 66.9%
    • Step 3.5 Flash 2603: —

Math

  • AIME 2025

    Competition mathematics, 2025 problems

    • GPT 5.2: 51.0%
    • Step 3.5 Flash 2603: —

Legacy evaluations

  • Terminal-Bench Hard

    Earlier terminal task suite

    • GPT 5.2: 31.8%
    • Step 3.5 Flash 2603: 32.6%Top

  • τ²-Bench Telecom

    Tool use in a customer-support simulation

    • GPT 5.2: 46.5%
    • Step 3.5 Flash 2603: 87.4%Top

  • AA-LCR (unversioned)

    Long-context reasoning, earlier grading

    • GPT 5.2: 45.7%
    • Step 3.5 Flash 2603: 63.0%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.

Prompt cache hits
48.7%
About $0.98 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": "openai/gpt-5.2",
    "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="openai/gpt-5.2",
    messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)

OpenAI

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