Grandmaster Coding
With a 2727 ELO on Codeforces, openai o3 outperforms 99% of human competitive programmers, making it the premier choice for autonomous refactoring and complex unit testing.
o3 / file-analysis
openai o3 is the latest reasoning powerhouse, designed for frontier-level STEM tasks and complex coding. With a 200k context window and configurable reasoning effort, it sets new benchmarks in cognitive depth for developers.
$ 1.8
$ 2
file
$ 7.2
$ 8
text
API
File Analysis
curl --request POST "https://gptproto.com/v1/responses" \
--header "Authorization: Bearer $GPTPROTO_API_KEY" \
--header "Content-Type: application/json" \
--data '{
"model": "o3",
"input": [
{
"role": "user",
"content": [
{
"type": "input_text",
"text": "what is in this file?"
},
{
"type": "input_file",
"file_url": "https://tos.gptproto.com/resource/gptproto.pdf"
}
]
}
]
}'Key Features of openai o3
The technical specifications that set openai o3 apart from standard LLMs.
ARC-AGI Performance
Reaching 87.5% on the ARC-AGI leaderboard, openai o3 demonstrates fluid intelligence, showing it can learn new rules in-context rather than just relying on pre-trained patterns.
Reasoning Effort Control
Developers can configure openai o3 to use low, medium, or high reasoning effort, providing granular control over the tradeoff between thinking time and logical depth.
SOTA STEM Reasoning
openai o3 achieved 90.2% on the AIME 2024 math competition, representing a massive leap in AI's ability to solve complex, multi-step symbolic logic and advanced mathematics.
How to Get a o3 API Key
Getting a o3 API key takes four steps and a few minutes. Create a free GPTProto account, add credits, generate your key, and make your first call — at $1.8 / $7.2 it's a cheaper o3 API key than going direct, and one key works across every model on the platform. Full o3 Documentation is in the docs.
Sign up
Create your free GPT Proto account to begin. You can set up an organization for your team at any time.
Top up
Your balance can be used across all models on the platform, including o3, giving you the flexibility to experiment and scale as needed.
Generate your API key
In your dashboard, create an API key — you'll need it to authenticate when making requests to o3.
Make your first API call
Use your API key with our sample code to send a request to o3 via GPT Proto and see instant AI-powered results.
Common Questions About openai o3
Get expert insights into deploying openai o3 for your technical reasoning projects.
How does openai o3 differ from the o1 series?
The openai o3 model is significantly faster and more capable than o1. While o1 established the reasoning paradigm, openai o3 achieves higher benchmarks in STEM, notably scoring 90.2% on AIME 2024 compared to 83.3% for o1. It also introduces a reasoning_effort parameter, allowing developers to choose between low, medium, and high compute tiers based on the complexity of the task and their specific latency requirements.
Can I control the thinking time of openai o3?
Yes, openai o3 supports a reasoning_effort parameter. By selecting 'low', 'medium', or 'high', you can balance the depth of the model's logical chain against the time it takes to respond. Higher effort levels are recommended for difficult math and coding tasks where accuracy is the priority, while lower effort is better for simpler logic where faster response times are needed.
Does openai o3 support image inputs?
Yes, openai o3 is a multimodal model. It can accept image inputs and provide text or code outputs based on its visual analysis. This is particularly useful for analyzing technical diagrams, identifying issues in circuit board layouts, or converting complex hand-drawn flowcharts into structured JSON or functional code snippets.
What are the token limits for openai o3?
The openai o3 model features a generous 200,000 token context window. It can output up to 100,000 tokens in a single request. It is important to note that the total output count includes 'hidden reasoning tokens'—the internal chain-of-thought used by openai o3. Developers should set max_completion_tokens high enough to accommodate both this internal thinking and the final visible response.
Is openai o3 suitable for real-time chatbots?
Generally, no. Because openai o3 is designed for deep reasoning, it has a higher 'time to first token' than standard models like GPT-4o. Even at 'low' reasoning effort, it takes several seconds to process its logic. We recommend using openai o3 for complex problem-solving, coding, and scientific research where accuracy outweighs the need for sub-second responses.
How is openai o3 billed on GPTProto.com?
Pricing for openai o3 follows a transparent structure: $15.00 per 1 million input tokens and $60.00 per 1 million output tokens. Internal reasoning tokens generated by openai o3 are billed at the output rate. GPTProto.com provides a unified credit pool, allowing you to access openai o3 and other models with a single balance and centralized logging for easier enterprise management.
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