Anthropic model product
Claude Mythos 5.1
1.
Updated Oct 23, 2026. Default version: Claude Mythos 5.1
LLMBoard Score73.0Claude Mythos 5.1
Coverage0%1 benchmark families
Context window1MTokens
Official input priceN/AOfficial price unavailable
Claude Mythos 5.1 Capability Profile
This profile uses the model's current scored version. Arena ratings and prices are shown separately.
Claude Mythos 5.1 Benchmark Results
Benchmark scores for Claude Mythos 5.1.
Sort by
Benchmark | Score | Rank | Participants | Percentile | Evidence | Evaluated |
|---|
| BenchmarkTerminal-Bench 4.0 | Score60.90% | Rank03 | Participants29 | Percentile92.86% | EvidenceC | Evaluated |
Claude Mythos 5.1 Arena Results
Preference and agent-evaluation results for the default version.
No Arena results
The default version does not have a matching Arena result yet.
Claude Mythos 5.1 Pricing
Official vendor API pricing appears first, followed by individual provider offers.
- Official API
- N/A
- Official provider
- N/A
- Lowest third-party
- N/A
- Tracked offerings
- 0
No provider prices
The default version has no current input or output token prices.
Official prices use only the vendor's configured official Provider and positive standard USD PAYG rates. Third-party offers remain explicitly labeled.
Claude Mythos 5.1 Runtime Performance
Provider-specific output speed and catalog latency for Claude Mythos 5.1. Runtime does not affect the capability score.
No runtime data
No provider-specific speed or latency record is linked to the default version yet.
Output Speed is generated output tokens received per second. Catalog latency is reported separately from observed provider TTFT.
Claude Mythos 5.1 Specifications
Technical details for the model's default version.
- Version
- Claude Mythos 5.1
- Released
- Sep 1, 2026
- Knowledge cutoff
- Unknown
- Parameters
- N/A
- Context window
- 1M
- Max output
- 128K
- Inputs
- image, text
- Outputs
- text
- Open weights
- No
- License
- Proprietary
Claude Mythos 5.1 Versions
Available versions of this model. The score column identifies the version used in the overall ranking.
Sort by
Version | Released | LLMBoard | Parameters | Context | Max output | Open weights | License |
|---|
| VersionClaude Mythos 5.1 | Released | LLMBoard73.02 | ParametersN/A | Context1M | Max output128K | Open weightsNo | LicenseProprietary |
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What is Claude Mythos 5.1?
Key information about Claude Mythos 5.1 and its available data.
1 is an Anthropic large language model deployment for reasoning and agentic work with text and image input, tool use, multilingual support, and a 1M-token context window. It is not generally available through the public Claude API as a cataloged model ID.
Data as of 2026-10-22.
FAQ
Common questions about Claude Mythos 5.1.
When was Claude Mythos 5.1 released?
Claude Mythos 5.1's default version was released on Sep 1, 2026.
How much does Claude Mythos 5.1 cost?
No official standard PAYG price is currently available for Claude Mythos 5.1.
Who created Claude Mythos 5.1?
Claude Mythos 5.1 was created by Anthropic.
What is the context window for Claude Mythos 5.1?
The default version has a 1M token context window.
Is Claude Mythos 5.1 open weight?
No. The default version is not marked as having publicly available weights.
How many API providers offer Claude Mythos 5.1?
No provider offering is currently linked to the default version.