Claude Opus 5.5 vs GPT-6 Astra. Price and specs.

For 10,000 requests of 2,000 tokens in and 500 out, Claude Opus 5.5 costs 44% less than GPT-6 Astra on Zurelay: $63.00 against $112.50. Both are below their labs' list prices: 65% for Claude Opus 5.5 and 75% for GPT-6 Astra.

Side by side

Specs and prices. Live.

Claude Opus 5.5 and GPT-6 Astra side by side
Claude Opus 5.5GPT-6 Astra
LabAnthropicOpenAI
ReleasedSep 22, 2026Sep 4, 2026
Context window1M tokens1.05M tokens
Max output128K tokens128K tokens
ReadsText, Images, PDFsText, Images, PDFs
Reasoning levelslow, medium, high, xhigh, maxlow, medium, high, xhigh, max
Price per 1M, in / out$1.40 / $7.00$2.50 / $12.50
Lab list price$4.00 / $20.00$10.00 / $50.00
Cached input per 1M$0.14$0.25
10K typical requests$63.00$112.50

Prices in US dollars per 1M tokens on Zurelay, live from the catalog. A typical request is 2,000 tokens in and 500 out. Output limits are each lab's.

What they're for

As each lab describes it.

Claude Opus 5.5

Claude Opus 5.5 is Anthropic's current Opus model, built for long-running agentic coding and knowledge work. The Zurelay Claude Opus 5.5 API serves it through an OpenAI-compatible or Anthropic-compatible endpoint at 65% below Anthropic's list price, for teams that want Opus-level results without Opus-level bills.

  • Coding agents
  • Codebase and document analysis
  • Knowledge work
Claude Opus 5.5 API

GPT-6 Astra

GPT-6 Astra is the top model in OpenAI's GPT-6 family, built for complex reasoning, coding, research and document work. The GPT-6 Astra API on Zurelay runs the same model through one OpenAI-compatible endpoint, below OpenAI's list price. It is for teams whose hardest tasks justify the most capable model.

  • Complex coding work
  • Research and analysis
  • Document creation
GPT-6 Astra API

Try both

Test on your own prompts.

Specs don't say which model handles your work better. Send the same requests to both and compare the answers, the tokens and the bill. On Zurelay that's a change of model name.

Every model from both labs is on Claude vs GPT. To price a whole month, use the LLM cost calculator.

compare.py
from openai import OpenAI
client = OpenAI(base_url="https://api.zurelay.com/v1", api_key="YOUR_ZURELAY_KEY")
prompt = [{"role": "user", "content": "Summarize this contract: ..."}]
# Same key, same code: only the model name changes
for model in ["claude-opus-5-5", "gpt-6-astra"]:
reply = client.chat.completions.create(model=model, messages=prompt)
print(model, reply.usage.total_tokens, reply.choices[0].message.content[:200])

FAQ

Claude Opus 5.5 vs GPT-6 Astra questions.

Anything else? Ask our team and we’ll answer by email.

Is Claude Opus 5.5 or GPT-6 Astra cheaper?

For 10,000 requests of 2,000 tokens in and 500 out, Claude Opus 5.5 costs 44% less than GPT-6 Astra on Zurelay: $63.00 against $112.50. Per 1M tokens, Claude Opus 5.5 is $1.40 input and $7.00 output, and GPT-6 Astra is $2.50 and $12.50.

Which has the bigger context window?

GPT-6 Astra, at 1.05M tokens, against 1M for Claude Opus 5.5.

Can I use Claude Opus 5.5 and GPT-6 Astra with one API key?

Yes. One Zurelay key calls both. With an OpenAI SDK, point it at https://api.zurelay.com/v1 and change only the model name, claude-opus-5-5 or gpt-6-astra, to switch.

Are these the real models?

Yes. Each model is served over several routes run by independent sellers, and every route is tested before it serves requests and every day after, with identity, dated-knowledge and reasoning checks that catch an older or different model sold under the name you asked for.

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