GPT-5.5 Pro
OpenAI · Highest-accuracy GPT-5.5 tier for slower, precision-heavy reasoning and coding
Key facts
- Provider
- OpenAI
- Context window
- 1.1M tokens
- Max output
- 128K tokens
- Input price
- $30 / M tok
- Output price
- $180 / M tok
- Knowledge cutoff
- Dec 1, 2025
- Released
- Apr 23, 2026
- License
- —
Capabilities
ReasoningTool callingStructured outputFile attachmentsTemperature controlOpen weights
Reasoning options
- effort medium · high · xhigh
Pricing
USD per million tokens, list API rates.
- Input
- $30
- Output
- $180
- Cache read
- —
- Cache write
- —
Modalities
- Input
- Text, Image, Pdf
- Output
- Text