NOUMENOpen app
NOUMEN

OpenAI · Efficient

GPT 5 Mini

Added Aug 7, 2025

Compare models

Choose up to 3 models to compare.1 of 3 chosen

Loading models…

Use in the app

A lightweight version of GPT-5 for cost-sensitive applications. Balances advanced capabilities with efficient resource usage.

  • Reasoning
  • Vision
Input
Text, Images
Output
Text
Reasoning effort
minimal · low · medium · high
Discovery tier
Efficient

Pricing

USD per 1M tokens
Input
$0.25
Output
$2.00
Cache read
$0.025

Reference prices as published by the model provider. API example

Specifications

Context window
400K
Max output
128K
Average output (7 days)
891 tokens
Longer than 67% of 465 models

Side by side

GPT 5 Mini compared

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

Compare models

Choose up to 3 models to compare.1 of 3 chosen

Loading models…

GPT 5 MiniOpenAIThis modelStep 3.5 Flash 2603stepfunRemove
ProviderOpenAIstepfun
Discovery tierEfficientOpen weights
AddedAug 7, 2025Apr 14, 2026
Limits
Context window400KBest262.14K
Max output128KBest65.54K
Average output891 tokens3K tokens
Pricing, USD per 1M tokens
Input$0.25$0.10Best
Output$2.00$0.30Best
Cache read$0.025—
Performance
Request success (24h)100.0%100.0%
Benchmark indexes
Intelligence Index16.817.0Best
Coding Index15.6—
Math Index90.7—
Capabilities
ReasoningYesYes
VisionYesNo
Reasoning effortminimal, low, medium, high—

Public evaluations

Benchmarks

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

  • GPT 5 Mini
  • Step 3.5 Flash 2603

Intelligence Index

  • GPT 5 Mini16.8
  • Step 3.5 Flash 260317.0

GPT 5 Mini tested at high reasoning effort

GPT 5 Mini: Better than 45% of 326 scored models

3.8Catalog models by score55.1

Indexes

  • Coding Index

    Composite of the coding evaluations

    • GPT 5 Mini: 15.6
    • Step 3.5 Flash 2603: —

  • Math Index

    Composite of the math evaluations

    • GPT 5 Mini: 90.7
    • Step 3.5 Flash 2603: —

Agentic work

  • AutomationBench-AA

    Workflow automation, penalized for guardrail violations

    • GPT 5 Mini: 6.5%
    • Step 3.5 Flash 2603: —

  • AutomationBench-AA tasks completed

    Workflows finished end to end without a guardrail violation

    • GPT 5 Mini: 0.9%
    • Step 3.5 Flash 2603: —

  • AA-Briefcasev1.1

    Agentic knowledge work, rated head to head

    • GPT 5 Mini: 428 Elo
    • Step 3.5 Flash 2603: —

  • GDPval-AAv2.1

    Economically valuable occupational tasks, rated head to head

    • GPT 5 Mini: 766 Elo
    • Step 3.5 Flash 2603: —

Document reasoning

  • GDP.pdf

    Professional reasoning over PDF documents, all-pass rate

    • GPT 5 Mini: 8.4%
    • Step 3.5 Flash 2603: —

  • AA-LCRv1.1

    Reasoning across long documents

    • GPT 5 Mini: 72.3%Top
    • Step 3.5 Flash 2603: 63.0%

  • MLCR-AA

    Long-context reasoning over medical records

    • GPT 5 Mini: 8.9%
    • Step 3.5 Flash 2603: —

Reasoning and knowledge

  • Humanity’s Last Exam

    Expert-level questions across academic fields

    • GPT 5 Mini: 21.5%
    • Step 3.5 Flash 2603: 24.5%Top

  • GPQA Diamond

    Graduate-level science questions

    • GPT 5 Mini: 82.8%Top
    • Step 3.5 Flash 2603: 82.6%

  • MMLU-Pro

    Multi-subject knowledge and reasoning

    • GPT 5 Mini: 83.7%
    • Step 3.5 Flash 2603: —

  • IFBench

    Following precise output instructions

    • GPT 5 Mini: 75.4%Top
    • Step 3.5 Flash 2603: 66.5%

Coding

  • Terminal-Benchv4.0

    Practical software engineering in a terminal

    • GPT 5 Mini: 0.0%
    • Step 3.5 Flash 2603: —

  • SciCode

    Scientific computing in Python

    • GPT 5 Mini: 39.0%
    • Step 3.5 Flash 2603: —

  • LiveCodeBench

    Recent competitive programming problems

    • GPT 5 Mini: 83.8%
    • Step 3.5 Flash 2603: —

Math

  • AIME 2025

    Competition mathematics, 2025 problems

    • GPT 5 Mini: 90.7%
    • Step 3.5 Flash 2603: —

Legacy evaluations

  • Terminal-Bench Hard

    Earlier terminal task suite

    • GPT 5 Mini: 33.3%Top
    • Step 3.5 Flash 2603: 32.6%

  • τ²-Bench Telecom

    Tool use in a customer-support simulation

    • GPT 5 Mini: 68.4%
    • Step 3.5 Flash 2603: 87.4%Top

  • AA-LCR (unversioned)

    Long-context reasoning, earlier grading

    • GPT 5 Mini: 72.3%Top
    • Step 3.5 Flash 2603: 63.0%

Scores from Artificial Analysis, updated Oct 26, 2026. GPT 5 Mini 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.

Prompt cache hits
22.1%
About $0.20 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-mini",
    "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-mini",
    messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)

OpenAI

Other OpenAI models, starting with the same family.