OpenAI removed the text chat limit on ChatGPT’s free tier this week, alongside a broader update that reworks which model powers the product for every paying and non-paying user. The changes land five weeks after OpenAI’s GPT-5.6 family reached general availability, and they arrive with a specific number attached to them: ChatGPT recently crossed one billion weekly users, a milestone OpenAI referenced directly when explaining the update.
What actually changed for each tier
Free and Go plan users are moving to GPT-5.6 Luna as their new default model, replacing GPT-5.5 Instant, and gaining unlimited text conversations without the rate limit that previously forced a wait once a session cap was reached. They are also getting a new Think button that triggers deeper reasoning for harder questions, subject to anti-abuse guardrails OpenAI did not detail publicly. Limits remain in place for everything outside plain text chat: file uploads, image generation, and voice all keep their existing caps.
Plus and Pro subscribers get a different change. Rather than switching between a separate Instant model and a separate reasoning model depending on the task, both are now handled by a single, updated GPT-5.6 Sol model, with a new slider letting users manually control how much computational effort ChatGPT puts into each response, from fast everyday answers up through more thorough analysis for coding, planning, and research. OpenAI says the goal was a model that delivers focused answers, adapts its level of detail to the question, and avoids unnecessary formatting regardless of how much reasoning effort it applies, eliminating what the company described internally as a jarring shift in tone that previously occurred when a conversation crossed from quick-answer mode into thinking mode. Notably, this update is scoped narrowly: the version of GPT-5.6 Sol used inside ChatGPT Work and Codex is explicitly unchanged, only the consumer chat experience is affected.
The accuracy numbers OpenAI is citing
OpenAI says internal testing across financial, medical, and legal prompts found factual errors dropped by roughly 62 percent with the new GPT-5.6 Luna and 68 percent with the updated GPT-5.6 Sol, compared against the prior GPT-5.5 Instant model. Those are OpenAI’s own internal figures rather than independently verified benchmark results, and the company has not published the specific test set or methodology behind them, so they’re worth treating as a company claim rather than a settled, externally reproduced number. Still, directionally they target exactly the failure mode that matters most for a model serving over a billion people weekly: confidently wrong answers on questions involving specific dates, numbers, sources, or rules, precisely the territory where AI hallucination tends to concentrate and where getting it wrong carries real consequences.
Why unlimited free access is a retention play, not a cost play
Removing the text-chat cap for free users is worth reading as a top-of-funnel and retention move rather than a cost-cutting one. It arrives after a year in which OpenAI has actually tightened usage limits in other parts of the product, and running an always-available free tier at over a billion weekly users is not a cheap decision from a compute-cost standpoint. The logic instead appears to be about keeping the free tier genuinely useful enough that people stay inside the ChatGPT ecosystem rather than bouncing to a competitor once they hit a wall mid-conversation, a friction point that has reportedly driven real churn toward rivals offering more generous free access.
The rollout itself is staggered. GPT-5.6 Luna became the default model for Free and Go users starting the week of the announcement, while the unlimited text-chat change and the new Think button followed roughly a week later. For Plus and Pro users, the updated GPT-5.6 Sol model and the new reasoning-effort slider began rolling out immediately across ChatGPT’s web, mobile, and desktop apps.
Part of a broader Sol, Terra, Luna naming shift
This update is a consumer-facing simplification pass rather than a new model generation. The underlying Sol, Terra, and Luna tier system was introduced in June, with Sol reaching general availability in July, and this week’s changes fold what had been a confusing choice, between separate Instant and Thinking modes, into a single model with adjustable effort instead. It also lands a month after OpenAI cut prices on the Luna and Terra tiers in late July, meaning the free and mid-tier models have now seen both a price cut and a capability upgrade within a matter of weeks, a combination that suggests OpenAI is prioritizing broad accessibility across its full user base rather than concentrating improvements only at the top of its subscription ladder.
How this compares to what rivals offer
The competitive backdrop matters here. Google’s Gemini already offers a genuinely capable free tier woven directly into Search, Gmail, and Docs, and Anthropic and xAI have both leaned on generous free access as part of their own growth strategies this year. A free tier that cuts a user off mid-conversation is a real point of friction in a market where switching to a competitor costs nothing but a new tab. Removing that friction for OpenAI’s largest, least monetized user segment is a defensive move as much as an offensive one: it protects the base ChatGPT has built rather than only trying to convert more of it to paid tiers.
The real cost this shifts, not eliminates
None of this makes free-tier inference free to run. OpenAI is absorbing real, ongoing compute cost to serve unlimited text conversations at a user base measured in the billions, a bet that only pays off if enough of those free users either convert to paid tiers over time or generate enough platform value, through engagement, data, and ecosystem lock-in, to justify the spend on their own. That calculation sits inside a much larger one: OpenAI’s overall infrastructure spending has scaled dramatically alongside its user growth this year, and a free tier this generous is only sustainable if the company’s broader unit economics continue trending the direction OpenAI’s public statements suggest they are.
What to actually watch next
The clearest signal of whether this update succeeds on its own terms will show up in two places over the coming weeks: whether OpenAI’s own accuracy claims hold up under independent testing once enough people have used the updated models at scale, and whether daily active usage among free-tier users actually increases now that the session-ending wall is gone. If the unlimited-access change meaningfully increases how often free users return, that’s a strong signal the friction really was costing OpenAI retention. If usage patterns stay roughly flat, it suggests the previous limits weren’t the binding constraint on engagement that this update assumes they were, and OpenAI absorbed a real, ongoing compute cost for a change that mostly benefits people who were already using the product heavily within the old limits anyway.
See Help Net Security’s original coverage for additional detail on the safety guardrails accompanying the rollout.




