Claude Fable 5 (batch) is $5 cheaper per 1M input tokens (50% lower; 2x difference).
API cost decision in 10 seconds
NewGPT-6 Astra Pro vs Claude Fable 5 (batch)
Pick Claude Fable 5 (batch) for lower cost; pick GPT-6 Astra Pro only if the larger context window matters more.
Page updated:
Data confirmed:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick Claude Fable 5 (batch) for lower cost; pick GPT-6 Astra Pro only if the larger context window matters more.
On the standard 1M input plus 500K output workload, Claude Fable 5 (batch) is estimated at $17.5 vs $35 for GPT-6 Astra Pro, saving $17.5 (50% lower).
Cost-first pickClaude Fable 5 (batch)
Context-first pickGPT-6 Astra Pro
Sample savings$17.550%
10x traffic gap$175
GPT-6 Astra Pro has more context, but Claude Fable 5 (batch) saves $17.5 on the standard workload. At 10x that traffic, the same price gap is about $175. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Claude Fable 5 (batch) stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | GPT-6 Astra Pro | Claude Fable 5 (batch) |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Claude Fable 5 (batch) | $75 | $37.5 |
| Balanced workload | 1M input + 1M output | Claude Fable 5 (batch) | $60 | $30 |
| Output-heavy chatbot | 1M input + 5M output | Claude Fable 5 (batch) | $260 | $130 |
Claude Fable 5 (batch) is $25 cheaper per 1M output tokens (50% lower; 2x difference).
GPT-6 Astra Pro has 50K more context (1.05x larger).
Claude Fable 5 (batch) is $17.5 cheaper on the standard workload (50% lower).
Estimate your workload cost
Your Workload Cost
This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.
Quick Decision
Claude Fable 5 (batch) has the lower input price; Claude Fable 5 (batch) has the lower output price; GPT-6 Astra Pro offers the larger context window. For the 1M input plus 500K output sample, Claude Fable 5 (batch) is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $35 for GPT-6 Astra Pro and $17.5 for Claude Fable 5 (batch).
Choose GPT-6 Astra Pro when you care most about larger context window.
Choose Claude Fable 5 (batch) when you care most about lower input-token price, and lower output-token price.
- On the standard 1M input plus 500K output workload, Claude Fable 5 (batch) is estimated at $17.5 vs $35 for GPT-6 Astra Pro, saving $17.5 (50% lower).
- Claude Fable 5 (batch) is $17.5 cheaper on the standard workload (50% lower).
- Claude Fable 5 (batch) is $5 cheaper per 1M input tokens (50% lower; 2x difference).
- Claude Fable 5 (batch) is $25 cheaper per 1M output tokens (50% lower; 2x difference).
- GPT-6 Astra Pro has 50K more context (1.05x larger).
| Feature | NewGPT-6 Astra Pro (OpenAI) | Claude Fable 5 (batch) (Anthropic) |
|---|---|---|
| Input Price prompt tokens per 1M | $10 | $5 |
| Completion Price per 1M tokens | $50 | $25 |
| Sample Workload Cost 1M input + 500K output | $35 | $17.5 |
| Context Window | 1.05M | 1M |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Claude Fable 5 (batch) | On the standard 1M input plus 500K output workload, Claude Fable 5 (batch) is estimated at $17.5 vs $35 for GPT-6 Astra Pro, saving $17.5 (50% lower). |
| High-volume input processing | Claude Fable 5 (batch) | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Claude Fable 5 (batch) | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | GPT-6 Astra Pro | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- gpt-oss-120b (free) can replace GPT-6 Astra Pro when lower sample workload cost matters most: $0.
- gpt-oss-20b (free) can replace GPT-6 Astra Pro when lower sample workload cost matters most: $0.
- gpt-oss-20b can replace GPT-6 Astra Pro when lower sample workload cost matters most: $0.1.
- gpt-oss-120b can replace GPT-6 Astra Pro when lower sample workload cost matters most: $0.12.
- Grok 4.20 Multi-Agent offers 2M context with $2.5 sample workload cost.
- Grok 4.20 offers 2M context with $2.5 sample workload cost.
- GLM 5.3 Flash offers 1.31M context with $0.2 sample workload cost.
- DeepSeek V4 Flash 0731 offers 1.31M context with $0.15 sample workload cost.
- GLM 5.3 Flash · Z.ai · #1
- GPT-5.6 Luna · OpenAI · #2
- DeepSeek V4 Flash 0731 · DeepSeek · #3
- Hy4 preview · Tencent · #4
Cheaper alternatives
Review low-cost models sorted by a standard 1M input plus 500K output workload.
Open cheapest modelsLarger context alternatives
Find models with larger context windows for RAG, long documents, and codebase review.
Open largest context modelsProvider catalogs
Compare models within provider hubs before choosing a final API vendor.
Open provider hubsOpenAI catalog
Review all tracked OpenAI models before deciding whether this matchup is the right shortlist.
Open OpenAI modelsAnthropic catalog
Check other Anthropic models with comparable pricing, context, or release timing.
Open Anthropic modelsGPT-6 Astra Pro is the same underlying model as [GPT-6 Astra](https://openrouter.ai/openai/gpt-6-astra), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode
Claude Fable 5 is a Mythos-class model from Anthropic, built for autonomous knowledge work and coding. It supports text, image, and file inputs with text output, with reasoning support and...