ChatGPT 5.1 vs ChatGPT 5: What’s New Today (Nov 12, 2025) — Features, Performance, Rollout, and Real‑World Advice
Published: November 12, 2025 Key takeaways (today) What changed in ChatGPT 5.1 vs ChatGPT 5? 1) Two models, one goal: smarter, more natural conversations 2) Measurable behavior shiftsOpenAI says 5.1 Thinking varies its reasoning time more dynamically than 5 Thinking—roughly twice as fast on the fastest tasks and twice as slow on the slowest—so you wait less for easy asks and get deeper analysis when it matters. On coding and math (e.g., AIME 2025, Codeforces‑style tasks), 5.1 Instant shows improved results while remaining responsive. OpenAI 3) Personalization that actually sticksBeyond presets (Default, Professional, Friendly, Candid, Quirky, Efficient, Nerdy, Cynical), you