gpt-5.5· Released Apr 24, 2026

Name: gpt-5.5
Brand: openai

openai/gpt-5.5

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token...

Input

From$4.125/M

Output

From$24.75/M

Context

Up to 1.1M

Max output

Up to 128K

Modalities

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Input and output show the lowest price across upstreams, for reference. Your actual prices are listed per upstream below.

Upstreams & pricing

Upstream	Context	Max output	Input $/1M	Output $/1M	Cached input $/1M
Zenlayer AI Gateway-openai_compat (Global)From price	1.1M	128K	≤272K$4.125 >272K$8.25	≤272K$24.75 >272K$37.125	≤272K$0.4125 >272K$0.825

Routed in real time — you pay the listed price of whichever upstream serves your call.

How to call

curlrequest.sh

curl https://api.tkex.ai/v1/chat/completions \
  -H "Authorization: Bearer $TX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "openai/gpt-5.5",
    "messages": [
      {"role": "user", "content": "Say hello in five words."}
    ]
  }'