OpenAI Upgrades Default Model to GPT-5.6 Luna, Granting Free Users Unlimited Conversations
0xBroomberg
OpenAI switched ChatGPT's default to GPT-5.6 Luna and opened unlimited text conversations to free users — the rapid expansion of the free tier is squeezing the differentiation case for paid plans.
What makes the new default model better?
GPT-5.6 Luna launched in early July, built for speed first.
Compared with the previous default GPT-5.5 Instant, the share of answers containing at least one factual error dropped 62%.
This means → the upgrade's core pitch is not "smarter" but "wrong less often" — for everyday users, accuracy is more noticeable than depth.
What do free users actually get?
Free and low-cost Go subscribers now have unlimited text conversations — no more usage caps.
Both tiers gain a new "Think" button that lets users switch to a higher reasoning mode on demand.
In plain terms = free users went from "can chat, but not much" to "chat all you want, and dial up the thinking when you need it."
What changes for paying subscribers?
Plus and Pro users move to GPT-5.6 Sol, tuned specifically for everyday conversation and tasks.
OpenAI says Sol delivers "more focused answers" with less formatting clutter, steadier tone, and fewer errors.
Paid users also get a slider tool to adjust how much thinking ChatGPT puts into each answer — less for simple questions, more for complex ones.
Why is the price dropping so fast?
OpenAI cut prices on Luna and Terra last week, only weeks after launch; previous models typically waited months before a price cut.
This reflects competitive pressure from low-cost open-source models forcing frontier labs to accelerate discounting.
This means → OpenAI is fighting on cost and capability at the same time — expanding features while slashing prices, at a pace that has shifted from quarterly to weekly.
If free keeps getting stronger, is paying still worth it?
The free tier's capabilities already exceed the daily needs of most ordinary users, further compressing paid plans' differentiation space.
How enterprise customers should budget for advanced AI capabilities remains an unresolved industry question.
In plain terms = the free version is good enough — what exactly the paid tier adds is a question OpenAI itself hasn't fully answered yet.
Content is for reference only, not financial advice.