OpenAI Defaults GPT-5.6 Luna for Free ChatGPT Users
Get the Tech newsletter
Daily tech — startups, AI labs, chips, the launches that shape the next decade. Free.
- OpenAI made GPT-5.6 Luna the default model for free ChatGPT users and unlocked unlimited text chats, plus a "Think" button for harder questions on Free and Go tiers.
- OpenAI released an updated GPT-5.6 Sol that now powers both Instant and deep-reasoning chats for Plus and Pro subscribers, consolidating the two into one experience.
- GPT-5.6 Sol produced 68% fewer responses with factual errors than GPT-5.5 Instant in OpenAI's high-stakes factuality evaluation covering finance, medicine, and law.
- OpenAI added a reasoning-effort slider for Plus and Pro users, letting them tune how much computation each response uses, alongside the new Think toggle for free users.
- OpenAI cited meaningful safety gains for under-18 users as part of the rollout, with team members on X noting the deliberate work behind those protections.
Why it matters: Free-tier users now get unlimited access to a capable model plus reasoning controls, narrowing the practical gap between free and paid ChatGPT. The 68% drop in factual errors across finance, medicine, and law suggests OpenAI is positioning GPT-5.6 Sol for regulated professional work, not just consumer chat.
