OpenAI on August 6, 2026 moved its present mannequin era into ChatGPT’s free tier, asserting that GPT-5.6 Luna will turn out to be the default mannequin for Free and Go customers and that these customers will get limitless textual content chats. The announcement additionally ships an up to date GPT-5.6 Sol for Plus and Professional subscribers, retuned for on a regular basis dialog, throughout a service the corporate says 1 billion individuals use every week.
For paid customers, the up to date Sol is constructed to provide extra direct responses, use tighter formatting, and proper the person when easy settlement wouldn’t assist. One mannequin now powers each Immediate responses and deeper reasoning for Plus and Professional subscribers, changing what had been two experiences with distinct tones.
“GPT-5.6 Sol delivers extra targeted solutions, adapts its degree of element to the query, avoids pointless formatting, and presents a useful correction when merely agreeing wouldn’t be helpful,” the corporate mentioned.
On reliability, OpenAI studies that in an inner analysis of economic, medical, and authorized prompts requiring factual element, responses containing at the very least one factual error had been about 62% much less frequent with GPT-5.6 Luna and 68% much less frequent with GPT-5.6 Sol than with GPT-5.5 Immediate, the mannequin Luna replaces because the free default. The determine comes from OpenAI’s personal testing, not an unbiased analysis.
A slider for paid customers, a Suppose button totally free ones
Plus and Professional customers get a slider in ChatGPT on net, cellular, and desktop that units how a lot thought the mannequin places into a solution, from fast on a regular basis replies as much as prolonged effort for planning, analysis, writing, coding, and selections. Free customers as a substitute get a Suppose button, which supplies GPT-5.6 Luna extra time to work via more durable questions on a per-message foundation.
The limitless entry has outlined edges. It applies to textual content chats; limits stay for file uploads, photographs, and different instruments, and OpenAI notes the providing is topic to abuse guardrails. Luna turns into the Free and Go default in the course of the week of the announcement, with limitless textual content chats and the Suppose button following within the week of August 10, 2026. As a result of the up to date Sol is optimized for on a regular basis chats, it runs solely in ChatGPT’s Chat expertise; the model of GPT-5.6 Sol powering Work and Codex is unchanged.
GPT-5.6 by the numbers
All figures beneath are OpenAI’s personal, from the announcement and the household’s July launch supplies:
- 68% fewer responses containing at the very least one factual error from the up to date GPT-5.6 Sol versus GPT-5.5 Immediate, in an inner analysis
- 62% fewer for GPT-5.6 Luna on the identical measure
- 1 billion individuals utilizing ChatGPT every week, per the corporate
- 74.6 for GPT-5.6 Luna on the Synthetic Evaluation Coding Agent Index, as reported in OpenAI’s launch tables
The place Luna sits within the GPT-5.6 lineup
Luna is the smallest of three GPT-5.6 tiers OpenAI launched for common availability on July 9, 2026, alongside the flagship Sol and the mid-tier Terra. The launch submit describes Luna because the household’s quickest and most inexpensive mannequin, and says the three names are sturdy functionality tiers that may advance on their very own cadence reasonably than mounted variations.
In OpenAI’s reported outcomes, Luna scores 51.2 on the Synthetic Evaluation Intelligence Index and outperforms Anthropic’s Claude Opus 4.8 on the coding agent index. These are vendor-reported numbers, however they describe the mannequin now in entrance of ChatGPT’s largest person group: the free tier strikes from GPT-5.5 Immediate to a current-generation mannequin that OpenAI says makes far fewer factual errors, despite the fact that it trails GPT-5.5 on the launch-table benchmark indices (51.2 vs 54.8 on the AA Intelligence Index).
The GPT-5.6 rollout to date
The GPT-5.6 household arrived generally availability on July 9, 2026, after a restricted preview, with OpenAI pitching efficiency per greenback because the household’s defining trait. On July 30, 2026, three weeks after launch, OpenAI lower API costs on the 2 cheaper tiers, taking 80% off Luna and 20% off Terra.
The August 6, 2026 replace extends that low cost finish of the lineup to the buyer product itself. As soon as the staged rollout completes, ChatGPT’s free tier will run a current-generation mannequin by default, maintain textual content conversations going and not using a charge restrict, and put greater reasoning one faucet away behind the Suppose button.
