OpenAI · GPT-5

GPT-5.5 Pro

Generally availableText / reasoning model

OpenAI’s maximum-effort GPT-5.5 variant for the hardest reasoning — powerful, but with uncapped reasoning spend.

Yes — GPT-5.5 Pro is a real OpenAI model.

Released June 2026 by OpenAI, GPT-5.5 Pro is part of the GPT-5 family. It's available through OpenAI's API, and we run it on PromptFrenzy — the examples below are real, unedited generations it produced.

Maker

OpenAI

Released

June 2026

Input price

$30 / 1M

Output price

$180 / 1M

What is GPT-5.5 Pro?

GPT-5.5 Pro is the highest-effort variant of GPT-5.5, aimed at the most demanding reasoning and coding problems. It appears in our Three.js and SVG showdowns, where it produced some of the most ambitious code. We keep it out of our timed/cost-capped showdown lineup for one reason: its reasoning spend can’t be reliably bounded, so a single call can run long and cost more than its peers.

What GPT-5.5 Pro actually produces

Real, unedited outputs from GPT-5.5 Pro in our model showdowns — same brief, same constraints as every other model, one shot each.

1198s to generate77,723 output tokens

View this generation →From: Cyberpunk Alley in Three.js →

GPT-5.5 Pro output for Pelican on a Bicycle: Claude Fable 5 vs GPT-5.5 Pro vs Gemini 3.1 Pro

245s to generate16,150 output tokens

From: Pelican on a Bicycle →

See GPT-5.5 Pro compared head-to-head

Compare every model side-by-side

See how GPT-5.5 Pro stacks up against the other frontier models on the same brief.

Browse all model showdowns →