o3-pro review, price and benchmarks (2026)

legacy paid api reasoning

Provider

Statuslegacy

AA Intelligence Index32.5 (July 16, 2026 snapshot)

Releasedn/a

Context windown/a

Modalitiesn/a

API price $/1M (in / out)n/a

Speedn/a

AccessAPI (legacy reasoning line)

In one line

The 2025 deep-reasoning specialist - slow and dated now, but a milestone in chain-of-thought models.

Coding58

Reasoning66

Writing45

Agents & tools50

Category scores (0-100) are WhichAI blended ratings: public category leaderboards plus editorial judgment. Guidance, not official measurements.

Alternatives worth a look

Qwen3.5 397B (Alibaba) · AA 33.7Open weights (Apache 2.0)
Step 3.7 Flash (StepFun) · AA 30.3Open weights · API
Mistral Medium 3.5 (Mistral AI) · AA 29.9Open weights · Le Chat · API

Open o3-pro's official app ↗ Open in the WhichAI app Not sure? Take the 30-second finder

Artificial Analysis Intelligence Index, 2026 rebased scale (top models ≈ 55–60). Snapshot: July 24, 2026 (BenchLM mirror), retrieved July 26, 2026. Context, price and release data come from vendor pages and public pricing mirrors (retrieved July 19, 2026). Missing values are not published or not yet verified - shown as -. Sources are linked inside the app (Model guide and About > Methodology).