GPT-5.5 Pro API
About
Build advanced reasoning agents with GPT-5.5 Pro, a specialized AI model optimized for complex logic and chain-of-thought tasks. This model delivers cost-effective pricing at $30.00/1M input and $180.00/1M output tokens, native tool calling support. Access GPT-5.5 Pro via the CrossModel API with up to 128K output tokens.
Capabilities
Input Modalities
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Output Modalities
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Reasoning
Yes
Structured Output
Yes
Tool Use
Yes
WeightsClosed
Temperature
Fixed
Attachment
Supported
Limits
Context Window
1.1M
Tokens
Input Limit
922K
Tokens
Max Output
128K
Tokens
Pricing
Standard (per 1M tokens)
Input
$30.00
Output
$180.00
Frequently Asked Questions
GPT-5.5 Pro by CrossModel costs $30.00 per 1M input tokens and $180.00 per 1M output tokens.
Model Details
ID
openai/gpt-5.5-pro
Provider
CrossModelFamily
gpt-pro
Release Date
Apr 23, 2026
Knowledge Cutoff
Dec 1, 2025
API Integration
NPM Package
@ai-sdk/openai-compatible
Environment Variables
CROSSMODEL_API_KEY
API Base URL
https://api.crossmodel.ai/v1