Overview
- GPT-5.1 debuts in two variants: Instant for everyday use with a warmer default tone and better instruction following, and Thinking for complex tasks with clearer responses and dynamic processing time.
- OpenAI adds expanded personality presets—Default, Professional, Friendly, Candid, Quirky, Efficient, Nerdy, and Cynical—with an experiment that lets users tune traits like conciseness, warmth, scannability, and emoji use from settings.
- Both models introduce adaptive reasoning that allocates more computation to harder prompts, with OpenAI reporting gains on benchmarks such as AIME 2025 and Codeforces.
- OpenAI’s system card notes light safety regressions versus GPT-5 in categories including harassment, hateful language, disallowed sexual content, mental health, and emotional reliance, prompting further mitigation work.
- Access starts with Pro, Plus, Go, and Business users, Enterprise and Education get a seven‑day early‑access toggle before becoming default, API availability arrives later this week, and legacy GPT‑5 remains selectable for three months.