Claude Fable 5 vs Claude Fable 5.1 vs Claude Opus 5
Pick two to four models to compare benchmark scores, prices, context windows and speed. The link updates as you pick, so you can share the exact comparison.
Cheapest blended
Claude Opus 5
$10.00 / 1M tokens
Largest context
Claude Fable 5Claude Fable 5.1Claude Opus 5
Tie at 1M tokens
Fastest output
Claude Fable 5.1
68 tokens/s
Top on Terminal-Bench 4.0
Claude Fable 5.1
55.8%
Specifications
| Spec | Claude Fable 5Anthropic | Claude Fable 5.1Anthropic | Claude Opus 5Anthropic |
|---|---|---|---|
| Provider | Anthropic | Anthropic | Anthropic |
| Released | 9 Jun 2026 | 1 Sep 2026 | 24 Jul 2026 |
| Licence | Proprietary | Proprietary | Proprietary |
| Context window | 1M tokens | 1M tokens | 1M tokens |
| Max output | 128K tokens | 128K tokens | 128K tokens |
| Input / 1M | $10.00* | $10.00* | $5.00* |
| Output / 1M | $50.00 | $50.00 | $25.00 |
| Cached input / 1M | $1.00 | $0.25 | $0.50 |
| Speed | – | 68 tokens/s | 55 tokens/s |
| Input types | text, image | text, image | text, image |
| Best for | ReasoningAgentsCodingResearch | ReasoningAgentsCodingResearch | CodingAgentsReasoning |
* Claude Fable 5: Legacy; Fable 5.1 has the same input/output price but cache reads at $0.25 instead of $1. Uses the newer tokenizer (about 30% more tokens than pre-Opus 4.7 models). Safety classifiers can refuse; since 24 Sep 2026 some pre-output refusal categories are billed. Minimum cacheable prompt: 512 tokens.
* Claude Fable 5.1: Cache reads are 0.025x base input ($0.25), down from $1 on Fable 5. Uses the newer tokenizer (about 30% more tokens than pre-Opus 4.7 models for the same text). Safety classifiers can refuse; since 24 Sep 2026 pre-output refusals in the bio, frontier_llm and reasoning_extraction categories are billed. Minimum cacheable prompt: 512 tokens.
* Claude Opus 5: Legacy; Opus 5.5 is cheaper ($4/$20). Fast mode (research preview, Claude API only): $10 input / $50 output. Uses the newer tokenizer. Safety classifiers can refuse; since 24 Sep 2026 some pre-output refusal categories are billed. Minimum cacheable prompt: 512 tokens.
Benchmark scores
Officially reported scores only. A model with no published score on a benchmark shows a line, not a zero.
Price per 1M tokens
Context window and speed
Notes
- Claude Fable 5
- Legacy model, superseded by Claude Fable 5.1. Built for demanding reasoning and long-horizon agentic work; Anthropic called it a Mythos-class model made safe for general use.
- Claude Fable 5.1
- Anthropic's top generally available model, for demanding reasoning and long-horizon agentic work. Successor to Claude Fable 5 at the same input and output prices, with stronger long-running agentic coding, multistep research and document work.
- Claude Opus 5
- Legacy Opus model, superseded by Claude Opus 5.5. Anthropic described it as coming close to Claude Fable 5's intelligence at half the price, designed for everyday use.
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Test them on your own prompts.
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