Claude Fable 5.1 API pricing
Official Anthropic list price, last checked Oct 29, 2026. Updated Oct 29, 2026.
Claude Fable 5.1 costs $10 per 1M input tokens and $50 per 1M output tokens, cached input at $0.25, and a 1M-token context window, per Anthropic's official pricing page (checked Oct 29, 2026). It's a premium-priced model: number 77 of 77 by blended price ($20 per 1M tokens at a 3 to 1 input to output mix). On LMArena's Code Arena it ranks #5 of 50 models we price (relative score 76 out of 100). Cheaper pick: Claude Sonnet 5.5 scores 85 against 76 on the same board at $4 blended, 5.0x less.
Claude Fable 5.1 price per million tokens
| Claude Fable 5.1 price per million tokens | USD |
|---|---|
| Input | $10 |
| Cached input | $0.25 |
| Output | $50 |
| Blended, 3 parts input to 1 part output | $20 |
| Context window | 1M tokens |
Official note from Anthropic: Cache reads $0.25, 5-minute cache writes $12.50.
What Claude Fable 5.1 costs for real work
List-price estimates for a month, no discounts. Our math, not a quote: change the token counts in the plan vs API calculator.
| Workload | Tokens a month | Claude Fable 5.1 | GPT-6 Astra | Claude Opus 5.5 |
|---|---|---|---|---|
| Light: a side project or personal assistant | 2M in, 0.5M out | $45.00 | $45.00 | $18.00 |
| Medium: a small team or one product feature | 20M in, 5M out | $450 | $450 | $180 |
| Heavy: a production app | 200M in, 50M out | $4,500 | $4,500 | $1,800 |
| Medium with 80% of input cached | 20M in (16M cached), 5M out | $294 | $306 | $119 |
How Claude Fable 5.1 ranks on LMArena
Relative score: 100 is the top model we price on that board. Rank is among the models in our price table, not the full leaderboard.
| Board | Rank | Score /100 |
|---|---|---|
| Coding (Code Arena) | #5 of 50 | 76 |
| Chat (Text Arena) | #4 of 51 | 70 |
| Creative writing (Text Arena creative writing) | #3 of 51 | 58 |
| Roleplay and characters (Text Arena multi-turn) | #10 of 51 | 20 |
| Reasoning and math (Text Arena math) | #2 of 51 | 92 |
| Vision (Vision Arena) | #7 of 33 | 72 |
| Long documents (Document Arena) | #1 of 11 | 100 |
| Cheap bulk and agents (Agent Arena) | #3 of 34 | 80 |
Closest rivals to Claude Fable 5.1
The models nearest in price, other makers first. Ranks are on Code Arena, where we have them.
| Model | In / out | Blended | Verdict |
|---|---|---|---|
| GPT-6 Astra | $10 / $50 | $20 | GPT-6 Astra wins: same price, higher score. Compare |
| GPT-5.5 | $5 / $30 | $11.25 | GPT-5.5 for price, Claude Fable 5.1 for quality. Compare |
| GPT-5.6 Sol | $4 / $20 | $8 | GPT-5.6 Sol wins on price. Compare |
| Muse Wonder 1.0 | $4 / $20 | $8 | Muse Wonder 1.0 for price, Claude Fable 5.1 for quality. Compare |
Cheaper alternatives to Claude Fable 5.1
At least 40% cheaper blended, best LMArena score first.
| Model | In / out | Blended | Verdict |
|---|---|---|---|
| Claude Opus 5.5 | $4 / $20 | $8 | Claude Opus 5.5 wins on both. Compare |
| Claude Sonnet 5.5 | $2 / $10 | $4 | Claude Sonnet 5.5 wins on both. Compare |
| GPT-6.1 Sol | $2 / $10 | $4 | GPT-6.1 Sol wins on both. Compare |
More from Anthropic
- Claude Opus 5$5 in, $25 out per 1M
- Claude Opus 5.5$4 in, $20 out per 1M
- Claude Sonnet 5.5$2 in, $10 out per 1M
- Claude Haiku 5.5$0.10 in, $0.50 out per 1M
FAQ
How much does the Claude Fable 5.1 API cost per million tokens?
$10 per 1M input tokens and $50 per 1M output tokens, plus $0.25 per 1M for cached input, as of Oct 29, 2026. A typical 3 to 1 input to output mix works out to $20 per 1M tokens.
Does Claude Fable 5.1 charge more for long prompts?
Anthropic doesn't list a long-prompt surcharge for Claude Fable 5.1. Its pricing note says: Cache reads $0.25, 5-minute cache writes $12.50.
Is Claude Fable 5.1 cheaper than GPT-6 Astra?
About the same. A medium month (20M input and 5M output tokens) costs $450 on Claude Fable 5.1 and $450 on GPT-6 Astra at list price. On Code Arena, Claude Fable 5.1 ranks #5 and GPT-6 Astra #2.
How does Claude Fable 5.1 rank on LMArena?
On Code Arena it is #5 of 50 models we price, with a relative score of 76 out of 100. It ranks on 8 of 8 boards we track.
What is a cheaper alternative to Claude Fable 5.1?
Claude Opus 5.5 costs $4 in and $20 out per 1M tokens, about 2.5x less blended, and scores 100 on Code Arena against 76 for Claude Fable 5.1.
Where does this Claude Fable 5.1 price come from?
From Anthropic's official pricing page, which we check every day. This page was last checked Oct 29, 2026.