Last updated: 2026-09-17 — GPT-6 Astra shipped on September 3, 2026. This article was written before launch; the release status, pricing, context window, and model ID (
gpt-6-astra) are updated, while the "~10T MoE" parameter count is still an unconfirmed rumor — OpenAI has not published one. For the confirmed specs, see What Is GPT-6 Astra?.
Quick Answer
GPT-6 Astra was released on September 3, 2026, and OpenAI still hasn't published a parameter count. The circulating number is ~10 trillion parameters with a Mixture-of-Experts (MoE) architecture — but this remains rumor, not an official figure. What's more reliable than the exact number is what shipped: a flagship above GPT-5.6 Sol with native multi-agent coordination trained from pretraining, a ~1.05M-token context window, and a price that reflects its scale — $10 / $50 per million input / output tokens, roughly double Sol's $5 / $30.
What "MoE" Actually Means
A Mixture-of-Experts model doesn't run every parameter on every token. It routes each input to a subset of "experts" (specialized sub-networks):
- Total parameters can be huge (10T) — the full pool of experts.
- Active parameters per token are much smaller — only the experts chosen for that input fire.
So "10T parameters" ≠ "10T active per token." MoE gets you big-model capacity without big-model per-token cost — which is why frontier models keep scaling this way.
Why the 10T Figure Is Uncertain
- Even after the September 3, 2026 release, OpenAI hasn't published a parameter count for Astra.
- The number comes from leaks/industry reporting, not a model card.
- Even if directionally right, "10T" could be total vs. active, or off by a factor.
Treat it as a signal of scale, not a data-sheet spec. The confirmed facts are: native multi-agent coordination trained from pretraining, the 10 Lean 4-verified math proofs, a ~1.05M-token context window, and $10 / $50 per million tokens. For the full picture of the model itself, see What is GPT-6 Astra.
What Scale Implies (More Useful Than the Number)
- Capability — more total experts means more specialized capacity for the model to route into, which plausibly underpins the multi-agent and deep-reasoning claims (the verified math-problem results are the main public evidence).
- Cost — even with MoE's active-parameter efficiency, a 10T-scale flagship is expensive to serve; the $2,000-per-problem figure from the reveal and the shipped $10 / $50 per million tokens (roughly 2x GPT-5.6 Sol) are consistent with that (GPT-6 Astra pricing analysis).
- Latency — bigger models plus multi-agent coordination mean longer reasoning chains; plan for minute-scale timeouts and streaming.
The Practical Takeaway
Don't obsess over the exact parameter count — it doesn't change how you integrate. What matters:
- Astra is bigger and more expensive, so it's a "critical reasoning" resource, not a daily driver.
- It's OpenAI-compatible, so integration is a
base_url+ model-name change. - Route by task: Astra for the hard 20%, cheap tiers for the rest.
from openai import OpenAI
client = OpenAI(api_key="sk-moyiapi-xxxxxx", base_url="https://api.moyiapi.com/v1")
# model="gpt-6-astra" for the hardest reasoning; route everything else to cheaper tiers
FAQ
Q: Is 10 trillion parameters confirmed? No. It's rumor from industry reporting. Astra has shipped, but OpenAI still hasn't published a parameter count. Treat it as directional, not official.
Q: Does more parameters mean better? Not linearly. MoE active-parameter routing matters more than the total count, and capability is per-dimension — a 10T model can still underperform on tasks it wasn't optimized for.
Q: Is a 10T model too slow to use interactively? For simple tasks, possibly overkill — but MoE keeps per-token cost manageable. The real latency concern is multi-agent coordination, not raw size; use streaming and longer timeouts.
Summary
The ~10T MoE figure is rumor, but the direction is real: Astra is bigger, more expensive, and multi-agent. Don't chase the exact number — set up the access layer and route by task. Sign up for Moyi API to add Astra (gpt-6-astra) as your top reasoning tier.
Get Started
Moyi API — one key for Astra, whatever its real size turns out to be.