Claude Fable 5.2 vs GPT-6 Astra

Claude Fable 5.2 is 1.3x cheaper than GPT-6 Astra on our example workload, at list prices.

Side by side

MeasureClaude Fable 5.2GPT-6 Astra
ProviderAnthropicOpenAI
Input / 1M tokens$8.00$10.00
Output / 1M tokens$40.00$50.00
Output price ÷ input price5.0x5.0x
Blended / 1M (3:1)$16.00$20.00
Context window1M1.05M
≈ English words that fit750,000788,000
1,000 calls (2000+500 tok)$36.00$45.00
AA Intelligence Index6557
LMArena TextNot on LMArena yet1474
Blended $ per AA index point$0.246$0.351

List prices from official pages (Anthropic, OpenAI), verified 2026-11-10. Benchmarks from public leaderboards (Artificial Analysis, LMArena), not run by us. Word counts use the rough 0.75 words per token rule for English. "$ per index point" is our own arithmetic (blended price ÷ index score), a rough value-for-money signal, not a benchmark.

What real workloads cost

Four example request shapes, priced at list rates with no caching or batch discounts. Monthly figures assume 100,000 requests.

WorkloadClaude Fable 5.2GPT-6 AstraGap
Support chat reply
a short system prompt, recent chat history and a reply
$0.0360 each
$3,600.00 / mo
$0.0450 each
$4,500.00 / mo
1.3x
RAG answer
a question plus about 20K tokens of retrieved documents, and a cited answer
$0.1920 each
$19,200.00 / mo
$0.2400 each
$24,000.00 / mo
1.3x
10-step agent task
an agent loop of 10 model calls, each re-reading about 8K tokens of context and emitting a 400-token tool call
$0.8000 each
$80,000.00 / mo
$1.00 each
$100,000.00 / mo
1.3x
Long-report summary
one 200K-token document summarized into about 2K tokens
$1.68 each
$168,000.00 / mo
$2.10 each
$210,000.00 / mo
1.3x

When to pick each

  • Pick Claude Fable 5.2 when cost is the main constraint: at list prices it is 1.3x cheaper than GPT-6 Astra on a typical 2,000-in / 500-out call ($36.00 vs $45.00 per 1,000 calls).
  • Pick Claude Fable 5.2 when answer quality matters more than price: it scores 65 vs 57 on the Artificial Analysis Intelligence Index, and is also the cheaper model here, so it wins on both counts.
  • Pick GPT-6 Astra if a single prompt can exceed 1M tokens (about 750,000 English words): its window is 1.05M.
  • They come from different providers (Anthropic and OpenAI), so switching means a second API key, SDK and billing account, and tool-calling formats differ. Our schema converter outputs both formats from one JSON Schema.

Context and pricing limits

  • Claude Fable 5.2: 1M tokens of context. GPT-6 Astra: 1.05M. GPT-6 Astra holds 1.1x more.
  • GPT-6 Astra: Short-context (<=272K input) price. The prices above are this tier; check the official pricing page before committing.
  • Cached input, batch and off-peak discounts can cut real bills a lot and differ by provider; they are not included here.

FAQ

Is Claude Fable 5.2 cheaper than GPT-6 Astra?

Yes, on our 2000-in / 500-out example call it costs $0.0360 vs $0.0450, 1.3x less.

Which has the larger context window?

GPT-6 Astra, with 1.05M tokens vs 1M.

Which scores higher on benchmarks?

Claude Fable 5.2 scores 65 vs 57 on the Artificial Analysis Intelligence Index. LMArena Text: Claude Fable 5.2 not on LMArena yet, GPT-6 Astra 1474. Benchmarks are averages; test both on your own prompts.

Run your own numbers in the token cost estimator · Claude Fable 5.2 pricing · GPT-6 Astra pricing · All comparisons