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Claude Mythos 5.1 vs Gemini 3.8 Flash Cyber

Claude Mythos 5.1 and Gemini 3.8 Flash Cyber are closely matched at 45.2 and 42.4 on the LLM Stats Score.

Anthropic · Google · Updated for 2026

Which is better?

Claude Mythos 5.1 and Gemini 3.8 Flash Cyber are closely matched on the overall LLM Stats Score at 45.2 and 42.4.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude Mythos 5.1

  • you want predictable pricing at $10.00/M input and $50.00/M output

Choose Gemini 3.8 Flash Cyber

  • you want the most recent training data — it shipped Sep 2026

At a glance

The differences that matter most.

Claude Mythos 5.1
Anthropic
Gemini 3.8 Flash Cyber
Google
Core performance indexes
LLM Stats Score
45.2
#30
42.4
#47
Coding
37.4
#17
35.6
#24
Agents
34.2
#21
31.2
#28
Cost, coverage & limits
Benchmark wins
—
—
Input price
$10.00 / M
— / M
Output price
$50.00 / M
— / M
Context window
1,000,000
—

Individual benchmarks

1 reported for Claude Mythos 5.1 · 4 for Gemini 3.8 Flash Cyber

No common benchmarks found

Claude Mythos 5.1 and Gemini 3.8 Flash Cyberdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Claude Mythos 5.1 specifies input context (1,000,000 tokens). Only Claude Mythos 5.1 specifies output context (128,000 tokens).

Anthropic
Claude Mythos 5.1
Input1,000,000 tokens
Output128,000 tokens
Google
Gemini 3.8 Flash Cyber
Input- tokens
Output- tokens
Tue Sep 08 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Mythos 5.1 supports multimodal inputs, whereas Gemini 3.8 Flash Cyber does not.

Claude Mythos 5.1 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Mythos 5.1

Text
Images
Audio
Video

Gemini 3.8 Flash Cyber

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Mythos 5.1

Proprietary

Closed source

Gemini 3.8 Flash Cyber

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Mythos 5.1 was released on 2026-09-01, while Gemini 3.8 Flash Cyber was released on 2026-09-02.

Gemini 3.8 Flash Cyber is 0 month newer than Claude Mythos 5.1.

Claude Mythos 5.1

Sep 1, 2026

1 weeks ago

Gemini 3.8 Flash Cyber

Sep 2, 2026

6 days ago

1d newer

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Claude Mythos 5.1 and Gemini 3.8 Flash Cyber side-by-side, then vote on the output you prefer.

Claude Mythos 5.1
✓ Preferred
Gemini 3.8 Flash Cyber
Open in Playground

FAQ

Common questions about Claude Mythos 5.1 vs Gemini 3.8 Flash Cyber.

Which is better, Claude Mythos 5.1 or Gemini 3.8 Flash Cyber?

Claude Mythos 5.1 and Gemini 3.8 Flash Cyber are closely matched on the LLM Stats Score at 45.2 and 42.4. Claude Mythos 5.1 is made by Anthropic and Gemini 3.8 Flash Cyber is made by Google. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Mythos 5.1 compare to Gemini 3.8 Flash Cyber in benchmarks?

Claude Mythos 5.1 scores Terminal-Bench 4.0: 60.9%. Gemini 3.8 Flash Cyber scores Gray Swan IPI Benchmark: 94.0%, CyberGym: 86.2%, Google Real-world Vulnerability Discovery: 71.0%, CWE-Bench: 47.2%.

What are the context window sizes for Claude Mythos 5.1 and Gemini 3.8 Flash Cyber?

Claude Mythos 5.1 supports 1.0M tokens and Gemini 3.8 Flash Cyber supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Mythos 5.1 and Gemini 3.8 Flash Cyber?

Key differences include LLM Stats Score (45.2 vs 42.4), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Mythos 5.1 and Gemini 3.8 Flash Cyber?

Claude Mythos 5.1 is developed by Anthropic and Gemini 3.8 Flash Cyber is developed by Google.

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