GPT-5.6-Cyber is a new cybersecurity-specific model designed to enhance advanced cyber capabilities. The model aims to equip defenders with frontier intelligence to counteract the growing threat of AI-driven cyberattacks.

Star Fleet is an AI system designed to solve complex open mathematics problems using Lean 4. It operates as a Mac desktop app, utilizing up to 20 custom agentic harnesses called "starships," each running a GPT-5.6 instance on a dedicated 60-vCPU server.

ChatGPT offers various plans including Free, Go, Plus, Pro, Business, and Enterprise, each with different levels of access to features. The flagship model GPT-5.3 has limited access, with restrictions on messages, uploads, image generation, deep research, memory, context, and Codex access.

GPT-5.4 mini and nano are newly released small models that enhance performance for high-volume workloads. GPT-5.4 mini offers over 2x faster processing and improved capabilities in coding, reasoning, multimodal understanding, and tool use, nearing the performance of the larger GPT-5.4 model in various evaluations.

GPT-5.4, now available in ChatGPT and the API, is the most capable and efficient frontier model designed for professional work. It combines advanced reasoning, coding capabilities from GPT-5.3-Codex, and enhanced agentic workflows for improved performance on complex tasks.

GPT-5.3-Codex-Spark is a new model optimized for real-time coding, capable of processing over 1000 tokens per second on ultra-low latency hardware. This model is a smaller version of GPT-5.3-Codex and represents the first milestone in a partnership with Cerebras.