For 10,000 requests of 2,000 tokens in and 500 out, GPT-6 Astra costs 29% less than Claude Fable 5.1 on Zurelay: $112.50 against $157.50. Both are below their labs' list prices: 65% for Claude Fable 5.1 and 75% for GPT-6 Astra.
Side by side
| Claude Fable 5.1 | GPT-6 Astra | |
|---|---|---|
| Lab | Anthropic | OpenAI |
| Released | Sep 1, 2026 | Sep 4, 2026 |
| Context window | 1M tokens | 1.05M tokens |
| Max output | 128K tokens | 128K tokens |
| Reads | Text, Images, PDFs | Text, Images, PDFs |
| Reasoning levels | low, medium, high, xhigh, max | low, medium, high, xhigh, max |
| Price per 1M, in / out | $3.50 / $17.50 | $2.50 / $12.50 |
| Lab list price | $10.00 / $50.00 | $10.00 / $50.00 |
| Cached input per 1M | $0.35 | $0.25 |
| 10K typical requests | $157.50 | $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
Claude Fable 5.1 is Anthropic's current Fable model, from the tier above Opus, built for demanding reasoning and long-horizon agentic work. The Zurelay Claude Fable 5.1 API serves it through OpenAI-compatible and Anthropic-compatible endpoints at 65% below Anthropic's list price, so your hardest jobs run for less.
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.
Try both
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.
from openai import OpenAIclient = 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 changesfor model in ["claude-fable-5-1", "gpt-6-astra"]: reply = client.chat.completions.create(model=model, messages=prompt) print(model, reply.usage.total_tokens, reply.choices[0].message.content[:200])For 10,000 requests of 2,000 tokens in and 500 out, GPT-6 Astra costs 29% less than Claude Fable 5.1 on Zurelay: $112.50 against $157.50. Per 1M tokens, Claude Fable 5.1 is $3.50 input and $17.50 output, and GPT-6 Astra is $2.50 and $12.50.
GPT-6 Astra, at 1.05M tokens, against 1M for Claude Fable 5.1.
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-fable-5-1 or gpt-6-astra, to switch.
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.
Create a key in seconds, point the SDK you already use at Zurelay, and every request costs up to 90% less from the first token.