o3
OpenAI · o-series
High-reasoning model optimized for difficult analysis, planning, and reliability-critical decisions.
Overview
Freshness note: Model capabilities, limits, and pricing can change quickly. This profile is a point-in-time snapshot last verified on February 15, 2026.
o3 is positioned for difficult reasoning-heavy tasks where accuracy and deep stepwise analysis matter more than low cost or raw throughput. Teams typically route hard decisions and complex planning workloads to this tier.
Capabilities
The model performs strongly on multi-step analysis, constraint-heavy planning, and ambiguity resolution. It is useful for high-stakes reasoning in engineering design, operations strategy, and risk evaluation.
Technical Details
o3 belongs to OpenAI’s reasoning-focused family and is often used as a specialized model rather than a universal default. It works best when prompts specify assumptions, constraints, and desired decision criteria.
Pricing & Access
Available through OpenAI API surfaces where reasoning-focused models are offered. Pricing and limits may change by product and account tier; verify current values before production budgeting.
Best Use Cases
Strong choice for architecture tradeoff analysis, migration planning, incident root-cause reasoning, policy interpretation, and other tasks where robust chain-of-thought-style reasoning is valuable.
Comparisons
Compared with GPT-5, o3 is often chosen for harder reasoning depth rather than broad general utility. Compared with DeepSeek-Reasoner, o3 may provide stronger integrated ecosystem support at potentially higher cost. Compared with Claude Opus 4.6, selection depends on reasoning style preference and platform alignment.