WhichAI / Models / GPT-5.5 Pro

GPT-5.5 Pro

· verified October 14, 2026

public paid api in Generator reasoning

Provider

Statuspublic

AA Intelligence Index~41.8 (not a current official measurement)

Released2026-04-24

Context window1.05M

Modalitiesn/a

API price $/1M (in / out)$30 / $180 (OpenRouter)

Speedn/a

AccessChatGPT Pro ($200/mo) · API

The score shown is a WhichAI estimate from adjacent benchmarks, not an official measurement.

In one line

Maximum-reasoning tier of GPT-5.5 - statistically tied with the very top on many boards. Overkill for everyday tasks.

Coding90

Reasoning91

Writing82

Agents & tools87

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

Alternatives worth a look

Claude Opus 4.8 (Anthropic) · AA 41.8Claude Pro $20/mo · API
GLM-5.3-Flash (Z.ai) · AA 41.8Released August 26, 2026 · open weights under MIT · API $0.15/$0.50 per 1M tokens · free chat at chat.z.ai
GPT-5.6 Terra (OpenAI) · AA 42.1Released July 9, 2026 · API $2.50/$15 per 1M tokens

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Artificial Analysis Intelligence Index, official scale (the number published on artificialanalysis.ai), relayed by OpenRouter and refreshed automatically: last read October 14, 2026. 209 models carry a current official measurement. A value marked ~ is converted from an earlier snapshot because no current measurement is published; an unmeasured model is never ranked. Context, price, modality and listing dates come from the public OpenRouter model list (refreshed automatically on the live site; static copy retrieved October 3, 2026) and vendor pages. Missing values are not published or not yet verified - shown as -. Sources are linked inside the app (the Ranking chapter and About > Methodology).