Checked October 9, 2026. GPT-6 Astra is OpenAI’s most capable model for demanding reasoning, coding, research and computer-use work. The API model ID is gpt-6-astra. OpenAI documents a 1,050,000-token context window, 128,000 maximum output tokens and an April 30, 2026 knowledge cutoff. 12
Current GPT-6 Astra specifications
| Item | GPT-6 Astra |
|---|---|
| API model | gpt-6-astra |
| Context window | 1,050,000 tokens |
| Maximum output | 128,000 tokens |
| Knowledge cutoff | April 30, 2026 |
| Reasoning levels | low, medium, high, xhigh, max |
| Standard input | $10 / 1M tokens |
| Cached input | $1 / 1M tokens |
| Cache write | $12.50 / 1M tokens |
| Standard output | $50 / 1M tokens |
Those rates apply to normal context lengths. Once a request contains more than 272K input tokens, OpenAI charges 2x input and cache rates and 1.5x output for the entire request. Long agent runs can therefore become materially more expensive even when their raw token count looks manageable. 23
Two reproducible API cost scenarios
OpenAI’s Standard pricing table and Astra model page distinguish short and long context. Above 272,000 input tokens, the higher rates apply to the full request. These examples assume ordinary, uncached tokens only (excluding tools, discounts, regional surcharges and sales tax).
| Single request | Astra | GPT-6.1 Sol |
|---|---|---|
| 100,000 input + 10,000 output | $1.50 | $0.30 |
| 300,000 input + 10,000 output (long context) | $6.75 | $1.35 |
For long context, Astra costs 0.3 × $20 input plus 0.01 × $75 output; GPT-6.1 Sol costs 0.3 × $4 plus 0.01 × $15. The higher rate applies to the whole request. These figures are price calculations, not measured agent spending or performance benchmarks.
Access is much broader than it was on launch day
Astra launched on September 3 with limited organizational access. That description is now stale. OpenAI lists Astra in the API, ChatGPT Work and Codex, while GPT-6 is rolling out in Chat to eligible Plus, Pro, Business and Enterprise accounts. 1456
GPT-6 Pro is a ChatGPT product powered by GPT-6 Astra rather than a separate open model family. OpenAI lists it for Pro $100, Pro $200, Business and Enterprise. Plus includes Astra in Work and Codex, but that is not the same product positioning as GPT-6 Pro. 45
Astra costs five times as much as GPT-6.1 Sol
Since late September, GPT-6.1 Sol has become the much cheaper alternative within the same generation. OpenAI lists Sol at $2 input / $10 output per million tokens and Astra at $10 / $50. Both have a 1.05M context window and 128K maximum output in the API catalog. 237
The price difference makes Astra a poor default for routine work. OpenAI positions GPT-6.1 Sol as near-Astra intelligence at one fifth of the price. Astra is more compelling when the hardest part of the workload is reliability on difficult tasks rather than raw token cost. 7
What the launch benchmarks establish
OpenAI’s launch material reports 98% on FrontierMath Tier 4, 99.9% on ARC-AGI-3 and 100% on ExploitBench. These are significant results, but they are first-party numbers. They do not replace an evaluation on the exact repositories, tools and task distributions used in production. 1
Cybersecurity is the most consequential capability change. OpenAI says Astra is its first broadly deployed model to reach the Critical cybersecurity threshold under the Preparedness Framework. That is a capability classification under appropriate tools and permissions, not a claim that ordinary Astra use is inherently dangerous. 8
GPT-6.1 Sol or GPT-6 Astra?
For many coding, analysis and agent tasks, GPT-6.1 Sol is the more sensible starting point: the same context class and maximum output at a much lower list price. Astra is the escalation option when failure is expensive or Sol repeatedly fails to finish the task reliably. 27
The useful metric is cost per successfully completed task. A model with a five-times higher token price can still be economical if it prevents retries, tool failures or expensive human correction. It is wasteful when Sol already completes the same job reliably.
Using GPT-6 Astra on a Mac
Astra does not run locally on Apple silicon. The 1.05M context figure describes the hosted service, not the memory requirement of downloadable weights. On macOS there are three practical access paths:
- ChatGPT Work or Chat where your plan has access,
- Codex with an eligible ChatGPT account,
- the OpenAI API using
gpt-6-astra.
There is no Ollama, MLX or llama.cpp deployment for Astra because OpenAI does not publish the model weights. 125
Minimal API example
You need an API key and the official Python SDK. Keep the key in an OPENAI_API_KEY environment variable, not in source code or your repository. Install the SDK first:
python3 -m pip install -U openai
from openai import OpenAI
client = OpenAI()
response = client.responses.create(
model="gpt-6-astra",
input="Review this design for logical contradictions and report only evidence-backed problems.",
reasoning={"effort": "high"},
)
print(response.output_text)
For long-context requests, the 272K pricing threshold should be part of the budget model. 23
When Astra is worth the premium
Astra is most relevant for long, multi-step work where failure is costly: large code changes, difficult research, computer use across several applications, complex document creation and high-stakes technical analysis. For routine chat, summaries and straightforward code edits, a cheaper GPT-6 model is usually the better baseline. 17
What Astra now means in the GPT-6 lineup
GPT-6 Astra is clearly specified: 1.05M context, 128K output, $10/$50 standard pricing and five reasoning levels. The main change since launch is product context. Astra is no longer only a limited rollout, and GPT-6.1 Sol now provides a substantially cheaper option in the same generation. 274
For Mac users, the decision is therefore not whether Astra fits in local memory. It is whether its higher success rate on the hardest tasks is worth the premium over Sol in the actual workflow.
Sources and evidence
Token prices and model limits come from OpenAI’s public documentation. Model benchmarks and safety classifications are provider-reported, without claiming independent laboratory replication.
Footnotes
Frequently Asked Questions
How much does GPT-6 Astra cost in the API?
Standard pricing is $10 per 1M input tokens, $1 per 1M cached input tokens and $50 per 1M output tokens. Requests above 272K input tokens use higher long-context rates.
How large is GPT-6 Astra context?
OpenAI documents a 1,050,000-token context window and up to 128,000 output tokens.
Is GPT-6 Astra available in ChatGPT?
GPT-6 is rolling out in Chat to eligible Plus, Pro, Business and Enterprise accounts. GPT-6 Pro is powered by Astra and is available on Pro $100/$200, Business and Enterprise; Plus also includes Astra in Work and Codex.
Can GPT-6 Astra run locally on a Mac?
No. Astra is a cloud model. On macOS you use it through ChatGPT, Codex or the OpenAI API; the model weights are not executed locally.
GPT-6 Astra or GPT-6.1 Sol?
Astra is OpenAI’s most capable model for the hardest work. GPT-6.1 Sol is much cheaper and is positioned close to Astra capability for many workloads. Both have 1.05M context and 128K maximum output.