❯ OpenAI Switches Free-Tier Default Model to GPT-5.6 Luna and Opens Unlimited Text Chat

FREE TIER SHAKEUPOpenAI is swapping the default model on ChatGPT’s free tier to GPT-5.6 Luna and, starting next week, opening unlimited text conversations to free users — the first time in ChatGPT’s three-year history that the free tier has dropped its message cap. Also launching alongside it is a Think button that lets users manually switch into reasoning mode for hard questions. Per Axios reporter Herb Scribner, limits on file uploads and image generation remain in effect.

PAID TIER UPDATEThe paid side is updating in tandem: both the Instant and Thinking paths for Plus and Pro users unify on the improved GPT-5.6 Sol, plus a new reasoning-intensity slider that lets users decide how much reasoning compute each answer burns. Sam Altman confirmed on X the same day that “5.6 Sol is much better in chat scenarios,” while Greg Brockman placed the update on the path to “making the product simpler over time.” The reasoning here isn’t complicated: for the past year, the free tier’s message wall has been ChatGPT’s most obvious shortfall against Gemini’s free tier and several free apps in China — and Luna, this generation of small models, has driven unit reasoning costs down to a level where dropping the cap is viable.

COMPETITIONWhat this shift really rewrites is the customer-acquisition cost baseline for free AI assistants. Teams building consumer AI apps have typically won users on “more generous free quotas” — a moat OpenAI has now filled in one move. The reasoning-intensity slider also hands part of the reasoning-budget decision to users, effectively admitting that a one-size-fits-all default reasoning tier is suboptimal on both cost and experience. Expect this design to be followed.

▪ SIGNALRemoving the free tier’s message cap is OpenAI trading falling inference costs for distribution — and taking away the best card its competitors had to play.