GPT-5.5
ChatNot available
OpenAI's latest frontier reasoning model with enhanced capabilities and 1M context window.
- Context
- 1.05Mtokens
- Max output
- 128Ktokens
- Latency
- ~20ms
- Released
- 2026-04
Pricing
$ / 1M tokensInput
$5.00/M
Output
$30.00/M
Cache Read
$0.50/M
Cache Write
$5.00/M
Capabilities
4 listed- Chat
- Tool Use
- Vision
- Coding
Code examples
POST /v1/chat/completionspython
from openai import OpenAI
client = OpenAI(
api_key="your_api_key",
base_url="https://api.modelstack.cc/v1",
)
response = client.chat.completions.create(
model="gpt-5.5",
messages=[{"role": "user", "content": "Hello!"}],
)
print(response.choices[0].message.content)Related models
Frequently asked questions
How is GPT-5.5 billed on ModelStack?expand_more
ModelStack bills based on actual request usage. Input, output, cache, and any other applicable rates follow the live pricing table on this page. Final request costs are available in the console.
What are the context window and maximum output for GPT-5.5?expand_more
GPT-5.5 has a 1.05M context window and supports up to 128K of output.
How can I call GPT-5.5 through ModelStack?expand_more
Use the model ID `gpt-5.5` with any OpenAI-compatible SDK pointed at the ModelStack API — see the code examples above for Python, Node.js, and cURL.
Which capabilities does GPT-5.5 support?expand_more
GPT-5.5 supports: Chat, Tool Use, Vision, Coding.