ChatGPT-5.6
It happened: after two weeks gated to government-approved partners, all three GPT-5.6 models — Sol, Terra and Luna — went public Thursday, Jul 9. Sol ships a new max reasoning effort and an ultra mode that fans hard problems out to subagents; OpenAI’s own numbers put Sol Ultra at 91.9% on TerminalBench 2.1, ahead of Claude Mythos 5’s 88.0. It landed the same day as Grok 4.5 and Meta’s surprise Muse Spark 1.1 — three frontier drops in one day. OpenAI’s next flagship, GPT-6 Astra, followed on Sep 3, and the tiers that succeed Sol and Luna, GPT-6 Sol and GPT-6 Luna, on Sep 22.
Leaks & news, newest first.
It’s live: Sol, Terra and Luna are public
Right on schedule, all three GPT-5.6 variants opened to the public. Sol is the deep-reasoning flagship, shipping a new max reasoning effort and an ultra mode that fans hard problems out to subagents; Terra is the everyday tier pitched at GPT-5.5-level quality for half the cost; Luna is the fast, low-cost workhorse. OpenAI’s published numbers put Sol Ultra at 91.9% on TerminalBench 2.1 against Claude Mythos 5’s 88.0 — with plain Sol at 88.8 clearing it too. It landed the same day as Grok 4.5 and Meta’s surprise Muse Spark 1.1: three frontier drops in one day. via OpenAI · Dataconomy
It's official: Sol, Terra and Luna all go public Thursday, Jul 9
OpenAI confirmed the Thursday, Jul 9 launch of all three GPT-5.6 variants after the administration granted permission for a wider release, following additional testing and further meetings with the company. Pricing is out too: Sol at $5/$30 per million tokens in/out, Terra at $2.50/$15 — pitched at GPT-5.5-level performance for half the cost — and Luna at $1/$6. It lands the same day Grok 4.5 goes public. via Engadget · Neowin
The daily market piles onto Thursday
Polymarket's day-by-day book now puts 64% on Jul 9 — by far the heaviest single day — with 98% on a July release overall. Traders are reading OpenAI's "coming weeks" as "this week."
A pending executive order may formalize the review that's holding it
POLITICO reported the administration is weighing an executive order establishing a formal evaluation process for frontier models — the same framework under which OpenAI agreed to stagger GPT-5.6. The report noted the rollout went to a small group at the request of the White House, OSTP, and ONCD, over Sam Altman's objections. via POLITICO
Altman internally: restrictions "shouldn't be the norm"
Altman told employees the restricted release is "not our preferred long-term model" and that OpenAI would push for a more sustainable approach for future launches. via TechCrunch
GPT-5.6 previewed: Sol, Terra and Luna — but only for approved partners
OpenAI unveiled the family — Sol (flagship), Terra (balanced), Luna (fast/low-cost) — available only to a "small group of trusted partners" per the U.S. government's request, the first pre-release federal gate on a frontier model. OpenAI called it a short-term step on the path to broader availability "in the coming weeks." via VentureBeat · Axios · Business Standard
The official word.
"This preview is a short-term step that puts GPT-5.6 on the path to broader availability in the coming weeks."
OpenAI, GPT-5.6 preview announcement · Jun 26, 2026
$4 / $20 per million tokens, on OpenAI's own API.
How much does ChatGPT-5.6 cost?
OpenAI's own API lists ChatGPT-5.6 (gpt-5.6) at $4 per million input tokens and $20 per million output tokens, and $0.40 per million cached input tokens. Prompts over 272K tokens cost $8 input and $30 output. Prices as published in the models.dev catalog, as of 2026-10-06.
What is ChatGPT-5.6's context window?
1.05M tokens, with up to 128K output tokens per response, as OpenAI lists ChatGPT-5.6 (gpt-5.6).
Listed by 43 providers, exact ids below.
43 providers list ChatGPT-5.6 in the models.dev catalog (as of 2026-10-06), under the model ids shown below.
gpt-5.6 · gpt-5.6-luna · gpt-5.6-solglobal.openai.gpt-5.6-luna · global.openai.gpt-5.6-sol · global.openai.gpt-5.6-terragpt-5.6-luna · gpt-5.6-sol · gpt-5.6-terragpt-5.6-luna · gpt-5.6-sol · gpt-5.6-terraopenai/gpt-5.6-luna · openai/gpt-5.6-luna-pro · openai/gpt-5.6-solopenai/gpt-5.6-luna · openai/gpt-5.6-luna-fast · openai/gpt-5.6-solgpt-5.6-luna · gpt-5.6-luna-pro · gpt-5.6-solgpt-5.6-luna · gpt-5.6-sol · gpt-5.6-terragpt-5.6-solgpt-5.6-luna · gpt-5.6-sol · gpt-5.6-terragpt-5.6-luna · gpt-5.6-sol · gpt-5.6-terragpt-5.6-lunaAlso listed by Cloudflare AI Gateway, Cortecs, CrossModel, Databricks, DevPass (LLM Gateway), DigitalOcean, Eden AI, GitHub Copilot, GitLab Duo, Impossibl, Infer by Flow7, Kenari, Kilo Gateway, LLM Gateway, Merge Gateway, NanoGPT, Neon, Ofox, OpenCode Go, OpenCode Zen, Opper, OrcaRouter, Pioneer, Requesty, routing.run, SAP AI Core, Snowflake Cortex, Venice AI, Vivgrid, Xpersona, ZenMux.
Listings cover the model family, so a provider may list a sibling tier under the same name. Check the id before you build on it.
Head to head, on the public leaderboards:
Sol answered. Hear the next one first.
ChatGPT-5.6 is live — this page is its drop record. The radar has already moved to what’s next: GPT-6.5, Gemini 4, the next Claude Opus and every other model on the board. Email + Chrome push free, SMS and a phone call on paid tiers.