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Claude Mythos 5.2 vs Grok-1.5

Claude Mythos 5.2 leads the LLM Stats Score 59.6 to -3.2.

Anthropic · xAI · Updated for 2026

Which is better?

Claude Mythos 5.2 leads the overall LLM Stats Score 59.6 to -3.2, ranking #2 overall.

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

Choose Claude Mythos 5.2

  • overall performance matters — it scores 59.6 and ranks #2 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you want the most recent training data — it shipped Nov 2026

Choose Grok-1.5

  • you are already invested in the xAI ecosystem

At a glance

The differences that matter most.

Claude Mythos 5.2
Anthropic
Grok-1.5
xAI
Core performance indexes
LLM Stats Score
59.6
#2
-3.2
#385
Reasoning
53.3
#8
-2.8
#375
Coding
45.1
#5
-1.0
#285
Cost, coverage & limits
Benchmark wins
—
—
Input price
$8.00 / M
— / M
Output price
$40.00 / M
— / M
Context window
1,000,000
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Claude Mythos 5.2
Grok-1.5
Vision
31.5#33
-5.5#235
Multimodal
31.7#29
-2.9#188
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

9 reported for Claude Mythos 5.2 · 9 for Grok-1.5

No common benchmarks found

Claude Mythos 5.2 and Grok-1.5don'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 5.2 specifies input context (1,000,000 tokens). Only Claude Mythos 5.2 specifies output context (128,000 tokens).

Anthropic
Claude Mythos 5.2
Input1,000,000 tokens
Output128,000 tokens
xAI
Grok-1.5
Input- tokens
Output- tokens
Tue Nov 10 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Mythos 5.2 supports multimodal inputs, whereas Grok-1.5 does not.

Claude Mythos 5.2 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Mythos 5.2

Text
Images
Audio
Video

Grok-1.5

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 5.2

Proprietary

Closed source

Grok-1.5

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Mythos 5.2 was released on 2026-11-09, while Grok-1.5 was released on 2024-03-28.

Claude Mythos 5.2 is 32 months newer than Grok-1.5.

Claude Mythos 5.2

Nov 9, 2026

0 days ago

2.6yr newer
Grok-1.5

Mar 28, 2024

2.6 years ago

Knowledge Cutoff

When training data ends

Claude Mythos 5.2 has a documented knowledge cutoff of 2026-06-01, while Grok-1.5's cutoff date is not specified.

We can confirm Claude Mythos 5.2's training data extends to 2026-06-01, but cannot make a direct comparison without Grok-1.5's cutoff date.

Claude Mythos 5.2

Jun 2026

Grok-1.5

—

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Mythos 5.2 and Grok-1.5 side-by-side, then vote on the output you prefer.

Claude Mythos 5.2
✓ Preferred
Grok-1.5
Open in Playground

FAQ

Common questions about Claude Mythos 5.2 vs Grok-1.5.

Which is better, Claude Mythos 5.2 or Grok-1.5?

Claude Mythos 5.2 leads the LLM Stats Score 59.6 to -3.2. Claude Mythos 5.2 is made by Anthropic and Grok-1.5 is made by xAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Mythos 5.2 compare to Grok-1.5 in benchmarks?

Claude Mythos 5.2 scores De novo protein binder design: 85.1%, Biomedical image analysis: 80.7%, Protocols Troubleshooting: 77.1%, Terminal-Bench-Science 0.1: 75.3%, Terminal-Bench 4.0: 70.5%. Grok-1.5 scores GSM8k: 90.0%, DocVQA: 85.6%, MMLU: 81.3%, HumanEval: 74.1%, MMMU: 53.6%.

What are the context window sizes for Claude Mythos 5.2 and Grok-1.5?

Claude Mythos 5.2 supports 1.0M tokens and Grok-1.5 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 5.2 and Grok-1.5?

Key differences include LLM Stats Score (59.6 vs -3.2), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Mythos 5.2 and Grok-1.5?

Claude Mythos 5.2 is developed by Anthropic and Grok-1.5 is developed by xAI.

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