GPT-5.5 Released: OpenAI’s Smartest Agent Model Yet
3 min readOpenAI just released GPT-5.5, its most capable model to date, rolling it out to paid ChatGPT subscribers and making it available in the API starting April 23, 2026. The company calls this a step toward “a new class of intelligence for real work.”
Unlike earlier models that excel at answering single questions, GPT-5.5 is built for agentic, multi-step tasks. Give it a complex problem and it plans, uses tools, checks its own work, and keeps going through ambiguity without needing constant guidance.
What Changed Between GPT-5.4 and GPT-5.5
OpenAI has been releasing models rapidly throughout 2026. GPT-5.4 arrived just weeks before GPT-5.5, reflecting the company’s accelerating iteration pace. Each version has layered on stronger coding, reasoning, and tool-use capabilities. GPT-5.5, codenamed “Spud” internally, continues that pattern but with a sharper focus on autonomous task execution.
The model is also being integrated with Codex, OpenAI’s software engineering agent, positioning it as one of the most capable coding tools available to developers right now.
What GPT-5.5 Can Do
According to OpenAI’s announcement, GPT-5.5 understands what users are trying to accomplish faster than previous models and carries more of the actual work itself. It excels at writing and debugging code, researching online, analyzing data, building documents and spreadsheets, and operating software tools end-to-end.
Performance benchmarks show GPT-5.5 matches GPT-5.4’s per-token latency in real-world serving while operating at a significantly higher level of intelligence. It also completes the same Codex tasks using fewer tokens, making it more efficient as well as more capable.
For API developers, GPT-5.5 is priced at $5 per million input tokens and $30 per million output tokens, with a 1M-token context window. The Pro variant runs $30 per million input tokens and $180 per million output tokens.
Why This Matters
The shift toward agentic AI is one of the defining trends of 2026. GPT-5.5 is not just answering questions. It is carrying out tasks. That distinction matters for businesses, developers, and everyday users who want an AI that handles multi-step workflows rather than single-shot prompts. OpenAI’s bet is that the model’s ability to plan and self-correct mid-task will reduce friction in real-world use cases that today still require significant human oversight.
OpenAI also shipped GPT-5.5 with its strongest safety package to date, drawing on feedback from nearly 200 trusted early-access partners and targeted testing across cybersecurity and biology risk vectors. As reported by TechCrunch, the company sees GPT-5.5 as a step toward a broader “super app” vision for ChatGPT. Watch for competitors like Anthropic, Google, and DeepSeek to respond with their own agentic model updates in the weeks ahead.
Who Gets Access
GPT-5.5 is rolling out now to ChatGPT Plus, Pro, Business, and Enterprise subscribers. It is also available in OpenAI’s Responses and Chat Completions APIs. The model is live today for developers building on the platform.