GPT 5.5 (Fast) API
About
Build advanced reasoning agents with GPT 5.5 (Fast), a specialized AI model optimized for complex logic and chain-of-thought tasks. This model delivers cost-effective pricing at $12.50/1M input and $75.00/1M output tokens, native tool calling support. Access GPT 5.5 (Fast) via the Vercel AI Gateway API with up to 128K output tokens.
Capabilities
Input Modalities
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Output Modalities
text
Limits
Context Window
1.0M
Tokens
Input Limit
872K
Tokens
Max Output
128K
Tokens
Pricing
Standard (per 1M tokens)
Input
$12.50
Output
$75.00
Caching (per 1M tokens)
Read
$1.25
Frequently Asked Questions
GPT 5.5 (Fast) by Vercel AI Gateway costs $12.50 per 1M input tokens and $75.00 per 1M output tokens. Cached reads cost $1.25 per 1M tokens.
Model Details
ID
openai/gpt-5.5-fast
Provider
Vercel AI GatewayFamily
gpt
Release Date
Apr 23, 2026
Knowledge Cutoff
Dec 1, 2025
API Integration