GPT-5.5
OpenAILarge Language ModelProprietaryOpenAI's most capable model, designed for long-horizon agentic tasks. Smarter and more token-efficient than GPT-5.4, excelling at coding, research, data analysis, and computer use.
Abilities
Use Cases
Available in Tools
Availability
How to Use
Pros
- OpenAI's smartest model — strongest on agentic coding, computer use, and knowledge work
- More token-efficient than GPT-5.4 — delivers better results with fewer tokens for most tasks
- 1M token context window — processes entire codebases and book-length documents
- Strong agentic capabilities — can research, write code, analyze data, and operate software end-to-end
- Broad third-party integration ecosystem — ChatGPT, GitHub Copilot, Cursor, Azure
Cons
- Expensive at $5/$30 per MTok — 2x the cost of GPT-5.4 ($2.50/$15)
- Long-context pricing surcharge — prompts over 272K tokens billed at 2x/1.5x
- Closed source — no model weights or training transparency
What to Use It For
Perfect For
Strongest GPT model for multi-step tasks requiring reasoning across large contexts and taking action over time
Top performance on agentic coding benchmarks — debugs, refactors, and builds features autonomously
Exceptional at early scientific research tasks with broad knowledge and strong reasoning
Good For
Strong comprehension and generation for complex business documents, strategies, and analysis
Improved computer use capabilities for automating browser and desktop workflows
Not Recommended
At $5/1M input, GPT-5.4 Mini ($0.75/1M) is 7x cheaper for bulk work
Try instead: GPT-4.1 Mini
Heavier reasoning makes it slower than GPT-5.4 for interactive applications
Try instead: GPT-4o
Do Not Use For
Closed source with no available weights — completely dependent on OpenAI API
Try instead: Llama 4 Maverick
LLM — text and vision understanding only, no image creation
Try instead: GPT Image 1, DALL-E 3