OpenAI o3
by OpenAI
Breakthrough reasoning model for complex math, science, and coding challenges
OpenAI's specialized reasoning model that 'thinks before it speaks' with explicit chain-of-thought. o3 excels at STEM problems, competitive programming, and multi-step reasoning.
Research teams, education platforms, or apps solving hard STEM problems
Frontier reasoning with explicit thinking process
At a Glance
- Category
- AI Models & APIs
- Pricing
- Usage-based, Pay-per-token, Tiered by effort level
- Target Market
- Research organizations, STEM education and tutoring, Competitive programming, Scientific computing, Complex problem-solving applications
- Deployment
- Cloud-only, API-based
- Founded
- 2015
- Headquarters
- San Francisco, CA
- Customers
- Research orgs, education platforms, quant firms
Key Features
- ✓Explicit reasoning
Shows full chain-of-thought process
- ✓STEM excellence
PhD-level math, physics, chemistry
- ✓Competitive programming
Frontier performance on coding challenges
- ✓Adjustable effort
Trade speed for quality (low/medium/high effort)
- ✓Breakthrough performance
State-of-the-art on reasoning benchmarks
Capabilities
Use Cases
- •STEM education and tutoring
Explain complex concepts with reasoning
PhD-level accuracy - •Competitive programming
Solve algorithmic challenges
Top 1% CodeForces performance - •Scientific research
Analyze complex scientific problems
- •Advanced mathematics
Solve graduate-level math problems
- •Multi-step reasoning
Complex logic and planning problems
Ideal For
Best For
- ✓Advanced mathematics and physics
- ✓Competitive programming (CodeForces, LeetCode)
- ✓Multi-step reasoning problems
- ✓Scientific research and analysis
- ✓PhD-level STEM questions
Integrations
Deployment
Market & Ratings
Research orgs, education platforms, quant firms
Leading reasoning-focused model
Competitive Analysis
Strengths
- ✓Best-in-class reasoning performance
- ✓Shows explicit thinking process
- ✓PhD-level STEM capability
- ✓Adjustable effort levels
- ✓State-of-the-art on math/science benchmarks
Weaknesses
- ✗Much more expensive than GPT-5.4
- ✗Slower inference (reasoning takes time)
- ✗No multimodal capabilities
- ✗No function calling
- ✗Overkill for most general tasks
Pricing
o3-mini
$1.10/1M input tokens, $4.40/1M output tokens
Faster reasoning model, good for most tasks
o3
$10/1M input tokens, $40/1M output tokens (medium effort)
Frontier reasoning, adjustable effort levels
o3 (high effort)
$20/1M input tokens, $80/1M output tokens
Maximum reasoning capability
Expensive vs GPT-5.4 but worth it for hard reasoning tasks. Effort levels: low (cheapest), medium (default), high (best quality).
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