Claude Fable 5.1 vs GPT-6 Astra: API cost
Official prices side by side, with worked examples.
All models, this workload
| Model | Per call | Per 1K calls | Min price / user |
|---|---|---|---|
| Gemini 2.5 Flash-Lite | $0.0004 | $0.4000 | – |
| GPT-6 Luna | $0.00045 | $0.4500 | – |
| Claude Haiku 5.5 | $0.00045 | $0.4500 | – |
| GPT-4o mini | $0.0006 | $0.6000 | – |
| GPT-5.6 Luna | $0.001 | $1.00 | – |
| GPT-5.4 nano | $0.00103 | $1.03 | – |
| Gemini 3.1 Flash-Lite | $0.00125 | $1.25 | – |
| GPT-5 mini | $0.0015 | $1.50 | – |
| Gemini 3.5 Flash-Lite | $0.00185 | $1.85 | – |
| Gemini 2.5 Flash | $0.00185 | $1.85 | – |
| Grok Build 0.1 | $0.003 | $3.00 | – |
| Gemini 3.8 Flash | $0.00337 | $3.38 | – |
| Gemini 3.6 Flash | $0.00337 | $3.38 | – |
| GPT-5.4 mini | $0.00375 | $3.75 | – |
| Grok 4.3 | $0.00375 | $3.75 | – |
| o4-mini | $0.0044 | $4.40 | – |
| Claude Haiku 4.5 | $0.0045 | $4.50 | – |
| Grok 4.7 | $0.007 | $7.00 | – |
| Gemini 2.5 Pro | $0.0075 | $7.50 | – |
| GPT-4.1 | $0.008 | $8.00 | – |
| GPT-6.1 Sol | $0.009 | $9.00 | – |
| GPT-6 Sol | $0.009 | $9.00 | – |
| Claude Sonnet 5.5 | $0.009 | $9.00 | – |
| Claude Sonnet 5 | $0.009 | $9.00 | – |
| Gemini 4 Argon | $0.009 | $9.00 | – |
| GPT-5.6 Terra | $0.0100 | $10.00 | – |
| Gemini 3.1 Pro Preview | $0.0100 | $10.00 | – |
| GPT-5.4 | $0.0125 | $12.50 | – |
| Claude Sonnet 4.6 | $0.0135 | $13.50 | – |
| GPT-5.6 Sol | $0.0180 | $18.00 | – |
| Claude Opus 5.5 | $0.0180 | $18.00 | – |
| Claude Opus 5 | $0.0225 | $22.50 | – |
| GPT-5.5 | $0.0250 | $25.00 | – |
| GPT-6 Astra | $0.0450 | $45.00 | – |
| Claude Fable 5.1 | $0.0450 | $45.00 | – |
Side by side
| Claude Fable 5.1 | GPT-6 Astra | |
|---|---|---|
| Input /1M | $10 | $10 |
| Cached /1M | $0.25 | $1 |
| Output /1M | $50 | $50 |
| Chat · 2K/500 ×1,000 | $45.00 | $45.00 |
| RAG · 20K/1K ×1,000 | $250 | $250 |
| Generation · 500/4K ×1,000 | $205 | $205 |
At 10K input / 1K output, Claude Fable 5.1 is cheaper. Price is one factor; test quality on your own prompts. Sources: Anthropic, OpenAI (2026-10-26).
Claude Fable 5.1: Cache read price; cache writes 1.25x (5m) / 2x (1h)
GPT-6 Astra: ≤272K input; long context $20/$75
Related
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Prices last checked 2026-10-26 against official sources · how we verify
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