Is Claude Fable 5.1 cheaper than GPT-6 Astra?
Per token, they cost the same. For an agent task (80,000 input tokens, 60,000 of them cached, and 6,000 output), Claude Fable 5.1 costs 8% less: $515 against $560 per 1,000 tasks.
API price comparison · Updated
Claude Fable 5.1 vs GPT-6 Astra pricing
Claude Fable 5.1 costs $10.00 per million input tokens and $50.00 per million output tokens; GPT-6 Astra costs $10.00 and $50.00. The list prices are identical, so caching, long prompts and token counts decide which costs less. For an agent task (80,000 input tokens, 60,000 of them cached, and 6,000 output), Claude Fable 5.1 costs $0.515 and GPT-6 Astra $0.560: Claude Fable 5.1 costs 8% less.
Compare your monthly cost on Claude Fable 5.1 and GPT-6 Astra
Estimated monthly cost
Claude Fable 5.1$5,500$0.055 per request
GPT-6 Astra$5,500$0.055 per request
Same cost for this workload. Excludes cache writes, tools and taxes.
Claude Fable 5.1 vs GPT-6 Astra prices per million tokens
| Price | Claude Fable 5.1 | GPT-6 Astra |
|---|---|---|
| Model ID | claude-fable-5-1 | gpt-6-astra |
| Input | $10.00 | $10.00 |
| Cache read | $0.25 | $1.00 |
| Cache write | $12.50 | $12.50 |
| Output | $50.00 | $50.00 |
| Batch in / out | $5.00 / $25.00 | $5.00 / $25.00 |
| Long prompts | Same rate | Over 272,000: $20.00 / $75.00 |
| Scheduled change | None announced | None announced |
| Status | Available | Available |
Prices for each provider’s own API, from Anthropic’s pricing page and OpenAI’s pricing page. The lower price in each row is highlighted. Ganivra uses these same rates to price Claude Fable 5.1 and GPT-6 Astra calls.
What one request costs on Claude Fable 5.1 and GPT-6 Astra
Worked out from the prices above at standard rates, with no Batch discount. Long-prompt rates apply where a model has them.
| Request | Claude Fable 5.1 | GPT-6 Astra | Per 1,000 requests | Difference |
|---|---|---|---|---|
| Chat reply3,000 input tokens, 500 output | $0.055 | $0.055 | $55.00 / $55.00 | Same cost |
| Document summary30,000 input tokens, 1,500 output | $0.375 | $0.375 | $375 / $375 | Same cost |
| Agent task80,000 input tokens (60,000 cached), 6,000 output | $0.515 | $0.560 | $515 / $560 | Claude Fable 5.1 costs 8% less |
| Long document300,000 input tokens, 2,000 output | $3.10 | $6.15 | $3,100 / $6,150 | Claude Fable 5.1 costs 50% less |
What changes which one costs less
- Prompt caching
- Cache reads cost $0.25 per million, 2.5% of the input price on Claude Fable 5.1, and $1.00 per million, 10% of the input price on GPT-6 Astra. The more of each prompt you reuse, the more this decides the bill.
- Cache writes
- Claude Fable 5.1 charges $12.50 per million tokens written to cache. GPT-6 Astra charges $12.50 per million tokens written to cache.
- Long prompts
- On Claude Fable 5.1, one rate at any prompt length. On GPT-6 Astra, prompts over 272,000 tokens cost $20.00 input and $75.00 output for the whole request. A 300 prompt costs $3.10 on Claude Fable 5.1 and $6.15 on GPT-6 Astra.
- Batch API
- Claude Fable 5.1 costs 50% less through the Batch API: $5.00 input and $25.00 output. GPT-6 Astra costs 50% less through the Batch API: $5.00 input and $25.00 output.
- Token counts
- Anthropic and OpenAI use different tokenizers, so the same text becomes a different number of tokens. The model with the lower per-token price can still cost more per request; compare on your own prompts before switching.
Compare them on your own customers, not a sample request.
Ganivra prices every Claude Fable 5.1 and GPT-6 Astra call you make and adds it up by customer, feature and workflow, next to what each customer pays. Switch a workflow and see what it did to each customer’s margin.
Claude Fable 5.1 vs GPT-6 Astra pricing questions
How much does Claude Fable 5.1 cost per million tokens?
$10.00 input and $50.00 output per million tokens on Anthropic's API, with cached input at $0.25 and Batch at $5.00 input and $25.00 output. The rate is the same at any prompt length.
How much does GPT-6 Astra cost per million tokens?
$10.00 input and $50.00 output per million tokens on OpenAI's API, with cached input at $1.00 and Batch at $5.00 input and $25.00 output. Prompts over 272,000 tokens cost $20.00 input and $75.00 output.
Which is cheaper for long prompts, Claude Fable 5.1 or GPT-6 Astra?
For a 300,000 input tokens, 2,000 output request, Claude Fable 5.1 costs $3.10 and GPT-6 Astra $6.15: Claude Fable 5.1 costs 50% less. On Claude Fable 5.1, one rate at any prompt length; on GPT-6 Astra, prompts over 272,000 tokens cost $20.00 input and $75.00 output for the whole request.
How do I compare Claude Fable 5.1 and GPT-6 Astra on my own traffic?
Record what each call actually used, then price the same usage on both models. Ganivra does this from your recorded calls: it shows what each customer, feature and workflow would cost on Claude Fable 5.1 and on GPT-6 Astra, next to what each customer pays you.
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