Chat with OpenAI o3 Now
What is OpenAI o3?
OpenAI o3 is a LLM developed by OpenAI, released on April 16, 2025, as a successor to the o1 series.
It represents a significant advancement in AI reasoning capabilities, designed to handle complex tasks across various domains.
OpenAI o3 integrates enhanced inference behaviors that allow it to simulate human-like thought processes, such as chain-of-thought reasoning and self-reflection, making it particularly effective for applications requiring deep problem-solving.
What’s New About OpenAI o3?
OpenAI o3 is powerful across coding, math, science, visual perception and more. It is a smart AI chat model with the ability to reason, which means that it can check its answers before giving you a final output.
This model performs especially strongly at visual tasks like analyzing images, charts, and graphics. OpenAI o3 makes 20% fewer major errors than OpenAI o1 on difficult, real-world tasks—especially excelling in areas like programming, business/consulting, and creative ideation.
Early testers emphasized its ability to generate and critically evaluate novel hypotheses—particularly within biology, math, and engineering contexts.
OpenAI o3 vs o3-mini vs o4-mini
Both OpenAI o3 and o4-mini were trained to think for longer before responding, while o3-mini is a smaller and more efficient version of the o3 model. Here is a breakdown of how they perform in key benchmarks:
| Benchmark | OpenAI o3 | o3-mini | o4-mini |
| AIME 2025 | 88.9% (no tools) | 86.5% | 92.7% (no tools) |
| Codeforces | 2706 (with terminal) | 2073 | 2719 (with terminal) |
| GPQA Diamond | 83.3% (no tools) | 77% | 81.4 (no tools) |
| MMMU | 82.9% | N/A | 81.6% |
| SWE-Bench Verified | 69.1% | 49.3% | 68.1% |
| Scale MultiChallenge | 56.51% | 39.89% | 42.99% |
Get Access to OpenAI o3
Accessing OpenAI o3 is easier than ever with multiple platforms offering integration for both casual users and developers.
Via HIX AI
For an easy and convenient experience, HIX AI provides free access to OpenAI o3. Simply visit the AI chat page, select the OpenAI o3 model, and begin chatting or generating responses.
In addition to OpenAI o3, HIX AI offers other OpenAI models like o1-mini, along with AI models from Claude and Gemini, making it a versatile hub for exploring various AI chat models in one place.
Through ChatGPT
Subscribe to ChatGPT paid plans to access o3 directly within the ChatGPT interface. This method is ideal for interactive use, where you can leverage o3's enhanced reasoning in real-time conversations.
Via OpenAI API
Developers can integrate OpenAI o3 through OpenAI API by signing up for an account, generating an API key, and meeting the required usage tiers. This offers programmatic access for building applications, with step-by-step tutorials available for setup and implementation.
Questions and Answers
What are the key features of OpenAI o3?
OpenAI o3 is designed for advanced reasoning in coding, math, science, and visual perception, with autonomous tool integration like web search, Python code execution, and image generation/manipulation. It uses reinforcement learning for strategic tool use and blended visual-textual chain-of-thought reasoning, enabling complex multi-step tasks.
When was OpenAI o3 released?
OpenAI o3 was publicly released on April 16, 2025, as the successor to o1, alongside o4-mini for cost-efficient applications. An enhanced o3-pro variant became available to Pro users in June 2025.
What is the difference between o3 and o4-mini?
OpenAI o3 is the flagship model for high-complexity tasks with superior performance on benchmarks, while o4-mini is a smaller, faster, and more affordable variant optimized for STEM reasoning and higher throughput. o4-mini replaces o3-mini and offers better instruction following and conversational naturalness.
How does OpenAI o3 perform on benchmarks?
OpenAI o3 achieves state-of-the-art results, including 69.1% on SWE-Bench, 88.9% on AIME 2025, 83.3% on GPQA Diamond, 82.9% on MMMU, outperforming o1 and other mini models in key areas. It reduces major errors by 20% on real-world tasks compared to predecessors.