Claude Fable 5.1 vs Claude Mythos 5.1
At a Glance
| Compare | Claude Fable 5.1Anthropic | Claude Mythos 5.1Anthropic |
|---|---|---|
| Intelligence, Cost, and Efficiency | ||
| IntelligenceHigher is better · MM Intelligence v4.4 | #2 of 5799.0 score · 3/3 sources · complete | UnrankedNot in the 57-model eligible cohort |
| CostLower is better · Published-token output estimate | #27 of 27$0.824 per LiveBench case | UnrankedNot in the 27-model eligible cohort |
| EfficiencyHigher is better · MM Efficiency v1.9 | #14 of 2749.5 score · 3/3 sources · complete | UnrankedNot in the 27-model eligible cohort |
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $10.00Anthropic ↗ · Sep 3, 2026 | $10.00Anthropic ↗ · Sep 2, 2026 |
| Output priceFrom · USD / 1M tokens | $50.00Anthropic ↗ · Sep 3, 2026 | $50.00Anthropic ↗ · Sep 2, 2026 |
| Context windowMaximum documented tokens | 1,000K | 1,000K |
| Model facts checked | Sep 2, 2026View model evidence → | Sep 2, 2026View model evidence → |
Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →
Available Benchmarks
Side-by-Side Facts
| Field | Claude Fable 5.1 | Claude Mythos 5.1 |
|---|---|---|
| Developer | Anthropic | Anthropic |
| Family | Claude 5 1 | Claude 5 1 |
| Model | Claude Fable 5.1 | Claude Mythos 5.1 |
| Version | Claude Fable 5.1 | Claude Mythos 5.1 |
| Lifecycle | active | active |
| Released | 2026-09-01 | 2026-09-01 |
| Knowledge cutoff | 2026-06-01 | 2026-06-01 |
| Input modalities | Text, Image | Text, Image |
| Output modalities | Text | Text |
| Context window | 1,000K | 1,000K |
| Total parameters | Unknown | Unknown |
| Active parameters | Unknown | Unknown |
| License | Unknown | Unknown |
| Open weights | No | No |
| API available | Yes | Yes |
| Self-hostable | No | No |
| Provider access | Anthropic (Standard) | Anthropic (Project Glasswing) |
| Capabilities | chat, generation, reasoning, tools | chat, generation, reasoning, tools |
Claude Fable 5.1 Capabilities
Claude Mythos 5.1 Capabilities
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Primary Evidence
Sources and Freshness
Questions
Claude Fable 5.1 vs Claude Mythos 5.1 FAQs
Is Claude Fable 5.1 or Claude Mythos 5.1 better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Claude Fable 5.1 and Claude Mythos 5.1, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, Claude Fable 5.1 or Claude Mythos 5.1?+
Claude Fable 5.1 is $10.00 and Claude Mythos 5.1 is $10.00 per million tokens, so they are tied on this metric. Claude Fable 5.1 is $50.00 and Claude Mythos 5.1 is $50.00 per million tokens, so they are tied on this metric.
Which has a larger context window, Claude Fable 5.1 or Claude Mythos 5.1?+
Both models have the same sourced context window: 1,000,000 tokens each.
Which performs better in benchmarks, Claude Fable 5.1 or Claude Mythos 5.1?+
There is no overall benchmark winner: At least two independently verified, protocol-matched benchmarks are required for an overall winner.
Can Claude Fable 5.1 or Claude Mythos 5.1 be self-hosted?+
Both models have the same sourced self-hosting status: unsupported. Claude Fable 5.1 is not marked open weight; Claude Mythos 5.1 is not marked open weight.
Can Claude Fable 5.1 and Claude Mythos 5.1 understand images?+
Claude Fable 5.1 is documented with image input; Claude Mythos 5.1 is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, Claude Fable 5.1 or Claude Mythos 5.1?+
Both models have the same sourced maximum output: 128,000 tokens each.
Do Claude Fable 5.1 and Claude Mythos 5.1 support reasoning and tool use?+
Claude Fable 5.1: reasoning, tool calling, and image input. Claude Mythos 5.1: reasoning, tool calling, and image input. Feature support does not establish relative quality.
Which is available from more inference providers, Claude Fable 5.1 or Claude Mythos 5.1?+
Claude Fable 5.1 has 1 sourced provider route; Claude Mythos 5.1 has 1, a tie.
Which offers better value, Claude Fable 5.1 or Claude Mythos 5.1?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.