Grandmaster Coding Power
Rated at ~2727 ELO on Codeforces, o3 is more capable than 99% of human programmers for refactoring and testing applications.
o3
o3 is OpenAI’s premier reasoning model, built for elite STEM tasks and advanced coding. With 200k context and high-effort logical thinking, o3 sets new benchmarks in math and complex problem-solving for developers on GPTProto.com.
$ 1.8
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$ 7.2
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API
Text To Text (Response)
curl --location 'https://gptproto.com/v1/responses' \
--header 'Authorization: GPTPROTO_API_KEY' \
--header 'Content-Type: application/json' \
--data '{
"model": "o3",
"input": [
{
"role": "user",
"content": [
{
"type": "input_text",
"text": "Write a short poem about artificial intelligence and its impact on humanity."
}
]
}
]
}'
Text to Text (Chat)
curl --location 'https://gptproto.com/v1/chat/completions' \
--header 'Authorization: GPTPROTO_API_KEY' \
--header 'Content-Type: application/json' \
--data '{
"model": "o3",
"messages": [
{
"role": "user",
"content": "Who are you?"
}
],
"stream": false
}'
o3 Standout Capabilities
Explore the core strengths that make o3 the most advanced reasoning model for STEM, coding, and logical planning on GPTProto.com.
Configurable Logic Effort
Balance speed and depth with the reasoning_effort parameter, tailoring o3 to your specific latency and cost needs.
Agentic Planning Precision
o3 offers high reliability in multi-step tool orchestration, significantly reducing failures in complex software environments.
Elite STEM Reasoning
o3 dominates math and science benchmarks, scoring 90.2% on the AIME 2024 and outperforming human experts in complex logic.
Build with o3 in Minutes
Follow these simple steps to set up your account, get credits, and start sending API requests to o3 via GPT Proto.
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.
OpenAI o3 Frequently Asked Questions
Further Reading
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