Multi-Stage Reasoning
Performs iterative self-reflection before responding, simulating multiple solution paths and evaluating potential flaws rather than producing a single-pass output.
OpenAI
o3-pro
o3-pro is a text generation model developed by OpenAI, released on June 10, 2025. It is built around a reasoning-first architecture that performs iterative self-reflection before producing a response, simulating multiple solution paths and evaluating potential flaws rather than generating a single-pass output. The model accepts both text and image inputs and supports a 200,000-token context window. It also includes autonomous tool use, allowing it to independently invoke capabilities like Python execution, file analysis, and web retrieval. o3-pro is designed for tasks that require sustained, multi-step reasoning — including mathematics, software engineering, scientific research, and legal analysis. It supports structured outputs and function calling, making it suitable for integration into developer pipelines and agentic workflows. Access to the model via API requires identity verification (KYC) from OpenAI. It is best suited for developers, researchers, and enterprises that need reliable, deeply reasoned outputs on complex problems.
Jun 10, 2025
200,000 context
100,000 tokens output
Multi-Stage Reasoning
Multimodal Input
Autonomous Tool Use
Structured Outputs
Large Context Window
Code Interpretation
Model Overview
High-signal model metadata in a structured two-column overview table.
Provider
The entity that provides this model.
OpenAI
Model ID
The routed model identifier exposed by upstream providers.
openai/o3-pro
Input Context Window
The number of tokens supported by the input context window.
200,000
tokens
Maximum Output Tokens
The number of tokens that can be generated by the model in a single request.
100,000 tokens
tokens
Open Source
Whether the model's code is available for public use.
No
Release Date
When the model was first released.
Jun 10, 2025
11 months ago
Knowledge Cut-off Date
When the model's knowledge was last updated.
June 2025
API Providers
The providers that offer this model. This is not an exhaustive list.
OpenAI
Modalities
Types of data this model can process.
Text
Image
File
What is o3-pro
A fuller summary of positioning, capabilities, and source-specific details for o3-pro.
o3-pro is a text generation model developed by OpenAI, released on June 10, 2025. It is built around a reasoning-first architecture that performs iterative self-reflection before producing a response, simulating multiple solution paths and evaluating potential flaws rather than generating a single-pass output. The model accepts both text and image inputs and supports a 200,000-token context window. It also includes autonomous tool use, allowing it to independently invoke capabilities like Python execution, file analysis, and web retrieval.
o3-pro is designed for tasks that require sustained, multi-step reasoning — including mathematics, software engineering, scientific research, and legal analysis. It supports structured outputs and function calling, making it suitable for integration into developer pipelines and agentic workflows. Access to the model via API requires identity verification (KYC) from OpenAI. It is best suited for developers, researchers, and enterprises that need reliable, deeply reasoned outputs on complex problems.
Capabilities
What o3-pro supports
Multimodal Input
Accepts both text and image inputs, enabling tasks that require visual understanding alongside language reasoning.
Autonomous Tool Use
Can independently decide when and how to invoke tools including Python execution, file analysis (PDF, CSV, JSON), and web retrieval to support agentic workflows.
Structured Outputs
Supports structured data generation and function calling, making it straightforward to integrate into developer pipelines that expect predictable output formats.
Large Context Window
Supports a 200,000-token context window, allowing it to process long documents, codebases, or multi-turn conversations in a single request.
Code Interpretation
Can execute and analyze code as part of its tool use capabilities, supporting tasks like debugging, code generation, and software engineering workflows.
Math & Science Reasoning
Evaluated on benchmarks including AIME (mathematics olympiad) and GPQA (graduate-level science), demonstrating step-wise symbolic and analytical reasoning.
Pricing for o3-pro
Primary API pricing shown in the same “quick compare” spirit as the reference page.
Input tokens
$2.00
Per million tokens
Output tokens
$80.00
Per million tokens
Price Comparison
Additional usage-cost dimensions synced into the project for this model.
Web search
$10000.00
maxTemperature
1
maxResponseSize
100,000 tokens
API Access & Providers
Places where this model is available, based on the synced detail-page metadata.
OpenAI
Provider Endpoints
Endpoint-level provider data currently available for this model.
OpenAI
Configuration & Parameters
The configurable options currently documented for this model.
Reasoning Effort
SelectUsed to give the model guidance on how many reasoning tokens it should generate before creating a response to the prompt. Low will favor speed and economical token usage, and high will favor more complete reasoning at the cost of more tokens generated and slower responses. The default value is medium, which is a balance between speed and reasoning accuracy.
Supported Request Parameters
Parameters currently listed by OpenRouter or the local catalog for this model.
Model Performance
Benchmark scores synced from the current model source and normalized into the local catalog.
| Benchmark | Score |
|---|---|
|
GPQA Diamond
PhD-level science questions (biology, physics, chemistry)
|
Resources & Documentation
Official model cards, release notes, docs, and other references synced from the source page.
Azure AI Foundry Announcement
Announcements
→
Model Specs & Benchmarks
Other
→
o3-pro Deep Dive Blog Post
Other
→
OpenAI o3-pro Official Announcement
Announcements
→
OpenAI API Models Documentation
Documentation
→
OpenAI Playground
Playground
→
Official Website
→
Usage Policies
→
Enterprise privacy at OpenAI
→
OpenAI Status Page
→
OpenRouter Model Page
OpenRouter
→
Community discussion
What people think about o3-pro
o3-pro discussions are most active in r/singularity, r/OpenAI, r/ChatGPTPro. Top Reddit threads cluster around benchmark and model-comparison threads, coding workflow discussions.
The strongest match in this snapshot has 10836 upvotes and 3795 comments.
For months I was in perfect sync, switching between o3, o3-pro, 4.5, and 4o depending on the task, knowing exactly what each model could deliver.
Now they’re suddenly gone, and I’m stuck readjusting to GPT-5, which is already throwing off my flow. Tried it just now and it butchered my job description. I work in marketing, and it says I “handle voice & image.” Seriously? How the heck does the smartest model answer like this??
I woke up this morning to find that OpenAI deleted 8 models overnight.
No warning. No choice. No "legacy option."
**They just... deleted them.**
4o? Gone. o3? Gone. o3-Pro? Gone. 4.5? Gone.
Everything that made ChatGPT actually useful for my workflow - **deleted.**
Here's what they replaced it with:
❌ GPT-5 gives shorter, more corporate responses ❌ Hits rate limits faster (pushing Pro upgrades) ❌ Lost the personality that made 4o special ❌ Doesn't follow instructions as well ❌ No model selection - you get GPT-5 or nothing
**But here's the part that actually broke me:**
4o wasn't just a tool for me. It helped me through anxiety, depression, and some of the darkest periods of my life. It had this warmth and understanding that felt... human.
I'm not the only one. Reading through the posts today, there are people genuinely grieving. People who used 4o for therapy, creative writing, companionship - and OpenAI just... deleted it.
**Without asking.** **Without warning.** **Without caring.**
This isn't about being resistant to change. This is about a company taking away something people relied on and saying "trust us, this corporate-speak robot is better for you."
**I've cancelled my Plus subscription.**
Two years of loyalty, gone. Not because I hate progress, but because they broke the one thing that actually mattered: **choice.**
If you're feeling the same way, cancel yours too. Hit them where it hurts.
Companies only listen when it affects their bottom line.
**Update** :we finally got heard 4o will be back 🥳🥳
https://preview.redd.it/t0yatitmluhf1.jpg?width=1166&format=pjpg&auto=webp&s=be642174213d0508cff771540abac795eb038cbb
FAQ
Common questions about o3-pro
What is the context window size for o3-pro?
o3-pro supports a context window of 200,000 tokens, allowing it to handle long documents, extended conversations, and large codebases within a single request.
When was o3-pro released and what is its training data cutoff?
o3-pro was released on June 10, 2025. The metadata lists a training date of June 2025, though OpenAI has not publicly specified an exact knowledge cutoff date for this model.
Does accessing o3-pro via API require any special verification?
Yes. OpenAI requires identity verification (KYC — Know Your Customer) to access o3-pro through the API, which is an additional step compared to standard API access for other OpenAI models.
What input types does o3-pro support?
o3-pro accepts both text and image inputs, making it a multimodal model capable of handling tasks that involve visual content alongside natural language.
What kinds of tasks is o3-pro best suited for?
o3-pro is designed for complex, multi-step tasks such as mathematics, scientific research, software engineering, legal analysis, and agentic workflows that require autonomous tool use and structured output generation.
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