o3 review, price and benchmarks (2026)

legacy paid api reasoning

Provider

Statuslegacy

AA Intelligence Index30.4 (September 8, 2026 snapshot)

Releasedn/a

Context windown/a

Modalitiesn/a

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

Speedn/a

AccessAPI (legacy)

In one line

Once the reasoning benchmark-setter; today mainly of historical and compatibility interest.

Coding55

Reasoning62

Writing42

Agents & tools48

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

Alternatives worth a look

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Gemma 4 31B (Google) · AA 29.4Open weights · runs on consumer hardware

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Artificial Analysis Intelligence Index, 2026 rebased scale (top models ~ 55-66). Snapshot: September 4, 2026 (BenchLM mirror), retrieved September 8, 2026. Specs and prices come from the OpenRouter public model list on the same date. Models nobody has measured carry no index score at all and never enter a ranking: where an estimate exists it is shown separately and labelled unmeasured. Context, price, modality and release dates come from the public OpenRouter model list (retrieved September 8, 2026) and vendor pages. Missing values are not published or not yet verified - shown as -. Sources are linked inside the app (Model guide and About > Methodology).