Anthropic model product
Claude Mythos
Claude Mythos Preview is an unreleased general-purpose frontier model from Anthropic, a new tier above Opus (internal codename 'Capybara').
Updated Aug 12, 2026. Default version: Claude Mythos Preview
LLMBoard score93.6Claude Mythos Preview
Coverage80%15 benchmark families
Context windowN/ATokens
Official input priceN/AOfficial price unavailable
Claude Mythos Specifications
Technical details for the model's default version.
- Version
- Claude Mythos Preview
- Released
- Unknown
- Knowledge cutoff
- Unknown
- Parameters
- N/A
- Context window
- N/A
- Max output
- N/A
- Inputs
- image, text
- Outputs
- text
- Open weights
- No
- License
- Proprietary
Claude Mythos Capability Profile
This profile uses the model's current scored version. Arena ratings and prices are shown separately.
Claude Mythos Benchmark Results
Benchmark scores for Claude Mythos Preview.
| CharXiv-R | 93.2% | 01 | 48 | 100.0% | C | |
| CyBench | 100.0% | 01 | 2 | 100.0% | C | |
| FigQA | 89.0% | 01 | 3 | 100.0% | C | |
| GPQA | 94.6% | 01 | 234 | 100.0% | C | |
| Humanity's Last Exam | 64.7% | 01 | 93 | 100.0% | C | |
| MMMLU | 92.7% | 01 | 49 | 100.0% | C | |
| SWE-bench Multilingual | 87.3% | 01 | 34 | 100.0% | C | |
| SWE-Bench Multimodal | 59.0% | 01 | 3 | 100.0% | C | |
| USAMO25 | 97.6% | 01 | 3 | 100.0% | C | |
| CyberGym | 83.1% | 02 | 11 | 90.0% | C | |
| SWE-Bench Pro | 77.8% | 02 | 45 | 97.7% | C | |
| SWE-Bench Verified | 93.9% | 02 | 105 | 99.0% | C | |
| Terminal-Bench 2.0 | 82.0% | 02 | 49 | 97.9% | C | |
| Graphwalks BFS >128k | 80.0% | 03 | 11 | 80.0% | C | |
| BrowseComp | 86.9% | 06 | 58 | 91.2% | C | |
| OSWorld-Verified | 79.6% | 07 | 23 | 72.7% | C |
Claude Mythos 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 Runtime Performance
Provider-specific output speed and catalog latency for Claude Mythos Preview. Runtime does not affect the capability score.
No runtime data
Browse runtime rankingsNo 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 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 Versions
Available versions of this model. The score column identifies the version used in the overall ranking.
| Claude Mythos Preview | N/A | 93.6 | N/A | N/A | N/A | No | Proprietary |
What is Claude Mythos?
Key information about Claude Mythos and its available data.
Claude Mythos Preview is an unreleased general-purpose frontier model from Anthropic, a new tier above Opus (internal codename 'Capybara').
It identified thousands of zero-day vulnerabilities across every major operating system and web browser as part of Project Glasswing, a cross-industry cybersecurity initiative with 12 partners including AWS, Apple, Microsoft, and Google. 1%), and Cybench (100% pass@1, saturated).
3x increase over the previous trendline for model performance. Deployed under ASL-3 Standard. Best-aligned Claude model to date per Anthropic's risk report, with the first-ever 24-hour internal alignment review before deployment. Not planned for general availability.
Pricing for participants: $25/$125 per million tokens (input/output). 244-page system card.
Data as of 2026-08-11.
Claude Mythos vs nearby models
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FAQ
Common questions about Claude Mythos.
When was Claude Mythos released?
A release date is not available for the default version.
How much does Claude Mythos cost?
No official standard PAYG price is currently available for Claude Mythos.
Who created Claude Mythos?
Claude Mythos was created by Anthropic.
What is the context window for Claude Mythos?
A context window is not available for the default version.
Is Claude Mythos open weight?
No. The default version is not marked as having publicly available weights.
How many API providers offer Claude Mythos?
No provider offering is currently linked to the default version.
What models should I compare Claude Mythos with?
Nearby ranked alternatives include Claude Opus 5, Claude Fable 5, GPT-5.6-Sol.