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GPT 5.5

openai/gpt-5.5

GPT 5.5 is a reasoning model by OpenAI with vision, function calling, prompt caching, structured output — designed for complex, multi-step problem solving where accuracy matters more than speed. It supports a 1.1M token context window with up to 128K tokens of output. Priced at $5 per million input tokens and $30 per million output tokens. Access GPT 5.5 through Inworld LLM Inference with OpenAI SDK compatibility, built-in failover, and intelligent routing across providers.

Input
$5.00
Output
$30.00
Cache read
$0.50
Context
1.1M
Max output
128K
TextImage→Text
Function CallingReasoningPrompt CachingStructured outputVision
Run on your server. Set INWORLD_API_KEY to your API key. Python requires pip install openai; JavaScript requires Node.js 18+; save it as example.mjs.
curl --fail-with-body https://api.inworld.ai/v1/chat/completions \
  -H "Authorization: Basic $INWORLD_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
    "model": "openai/gpt-5.5",
    "messages": [{"role": "user", "content": "Hello"}],
    "stream": true
  }'
Model GPT 5.5OpenAI SDK compatible

Pricing and providers

Access GPT 5.5 through Inworld LLM Inference or speech to speech via OpenAI. By using the providers below you agree to their terms, listed under each provider's name in the Legal section.

Modalities
OpenAIThis pageopenai/gpt-5.5
$5.00$30.00$0.50—1.1M128K
TextImage→Text
Prices in USD per 1M tokens.

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