Released on April 16, 2025, o3 and o4-mini are the latest additions to OpenAI’s o-series models, engineered to “think longer before responding.” These models represent OpenAI’s most advanced reasoning systems to date, capable of complex problem-solving across various domains.

🔍 Key Features
1. Advanced Reasoning Abilities
- o3: Excels in complex tasks involving coding, mathematics, science, and visual perception. It has set new benchmarks in various evaluations, including Codeforces and SWE-bench.
- o4-mini: Optimized for speed and cost-efficiency, it delivers remarkable performance in math, coding, and visual tasks, achieving high scores in AIME 2024 and 2025 evaluations.
2. Visual Input Integration
For the first time, these models can process and reason with visual inputs, such as images, charts, and graphics. This capability allows for a more comprehensive understanding and analysis of visual data.
3. Autonomous Tool Utilization
Both models can autonomously decide when and how to use various tools within ChatGPT, including:
- Web browsing
- Python execution
- Image and file analysis
- Image generation
- Canvas
- Automations
- File search
- Memory
This autonomy enables the models to tackle multifaceted questions more effectively, producing detailed and thoughtful answers efficiently.
🚀 Performance Highlights
- o3: Demonstrates a 20% reduction in major errors compared to previous models on complex, real-world tasks, particularly excelling in programming, business consulting, and creative ideation.
- o4-mini: Achieves a 99.5% pass rate on AIME 2025 when utilizing a Python interpreter, showcasing its effective tool integration and problem-solving capabilities.
📌 Availability
These models are now accessible to ChatGPT Plus, Pro, and Team users through the o3, o4-mini, and o4-mini-high versions. Support for o3-pro is expected to roll out in the coming weeks.
Learn more: Introducing OpenAI o3 and o4-mini from OpenAI