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Claude Mythos Preview vs Kimi K3.1 Pro

Claude Mythos Preview and Kimi K3.1 Pro are closely matched at 54.2 and 55.5 on the LLM Stats Score. Kimi K3.1 Pro is 12.5x cheaper per token.

Anthropic · Moonshot AI · Updated for 2026

Which is better?

Claude Mythos Preview and Kimi K3.1 Pro are closely matched on the overall LLM Stats Score at 54.2 and 55.5.

In the 4 individual benchmarks reported for both models, Claude Mythos Preview wins 3; this is a narrower head-to-head signal than the composite indexes.

On price, Kimi K3.1 Pro is roughly 12.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

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

Choose Claude Mythos Preview

  • you value its reported benchmark strengths — it wins 3 of 4 exact shared results

Choose Kimi K3.1 Pro

  • cost matters — it's about 12.5x cheaper per token

At a glance

The differences that matter most.

Claude Mythos Preview
Anthropic
Kimi K3.1 Pro
Moonshot AI
Core performance indexes
LLM Stats Score
54.2
#7
55.5
#5
Reasoning
55.1
#4
54.3
#6
Coding
44.1
#5
42.7
#9
Agents
36.8
#22
41.6
#5
Cost, coverage & limits
Benchmark wins
3 of 4
1 of 4
Input price
$25.00 / M
$2.00 / M
Output price
$125.00 / M
$10.00 / M
Context window
—
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
Claude Mythos Preview
Kimi K3.1 Pro
Math
47.6#1
38.6#26
Vision
40.0#5
40.5#4
Multimodal
37.1#7
40.8#2
Safety
19.8#10
24.5#5
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

16 reported for Claude Mythos Preview · 30 for Kimi K3.1 Pro

4 shared

Claude Mythos Preview outperforms in 3 benchmarks (CharXiv-R, GPQA, Humanity's Last Exam), while Kimi K3.1 Pro is better at 1 benchmark (BrowseComp).

Claude Mythos Preview shows notably better performance in the majority of benchmarks.

Thu Oct 29 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Kimi K3.1 Pro costs less

For input processing, Claude Mythos Preview ($25.00/1M tokens) is 12.5x more expensive than Kimi K3.1 Pro ($2.00/1M tokens).

For output processing, Claude Mythos Preview ($125.00/1M tokens) is 12.5x more expensive than Kimi K3.1 Pro ($10.00/1M tokens).

In conclusion, Claude Mythos Preview is more expensive than Kimi K3.1 Pro.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Thu Oct 29 2026 • llm-stats.com
Anthropic
Claude Mythos Preview
Input tokens$25.00
Output tokens$125.00
Best providerAnthropic
Moonshot AI
Kimi K3.1 Pro
Input tokens$2.00
Output tokens$10.00
Best providerUnknown Organization
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

Only Kimi K3.1 Pro specifies input context (1,048,576 tokens). Only Kimi K3.1 Pro specifies output context (1,048,576 tokens).

Anthropic
Claude Mythos Preview
Input- tokens
Output- tokens
Moonshot AI
Kimi K3.1 Pro
Input1,048,576 tokens
Output1,048,576 tokens
Thu Oct 29 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Mythos Preview and Kimi K3.1 Pro support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Mythos Preview

Text
Images
Audio
Video

Kimi K3.1 Pro

Text
Images
Audio
Video

Release Timeline

When each model was launched

Kimi K3.1 Pro was released on 2026-10-23, while Claude Mythos Preview's release date is not specified.

We can confirm Kimi K3.1 Pro's release timeline, but cannot make a direct age comparison without Claude Mythos Preview's release date.

Claude Mythos Preview

—

Kimi K3.1 Pro

Oct 23, 2026

2 days ago

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

Provider Availability

Claude Mythos Preview is available from Anthropic. Kimi K3.1 Pro is available from Moonshot AI.

Claude Mythos Preview

anthropic logo
Anthropic
Input Price:Input: $25.00/1MOutput Price:Output: $125.00/1M

Kimi K3.1 Pro

moonshot logo
Unknown Organization
Input Price:Input: $2.00/1MOutput Price:Output: $10.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Mythos Preview and Kimi K3.1 Pro side-by-side, then vote on the output you prefer.

Claude Mythos Preview
✓ Preferred
Kimi K3.1 Pro
Open in Playground

FAQ

Common questions about Claude Mythos Preview vs Kimi K3.1 Pro.

Which is better, Claude Mythos Preview or Kimi K3.1 Pro?

Claude Mythos Preview and Kimi K3.1 Pro are closely matched on the LLM Stats Score at 54.2 and 55.5. Claude Mythos Preview is made by Anthropic and Kimi K3.1 Pro is made by Moonshot AI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Mythos Preview compare to Kimi K3.1 Pro in benchmarks?

Claude Mythos Preview scores CyBench: 100.0%, USAMO25: 97.6%, GPQA: 94.6%, SWE-Bench Verified: 93.9%, CharXiv-R: 93.2%. Kimi K3.1 Pro scores BabyVision: 95.4%, GPQA: 94.2%, BenchCAD (with Python tool): 92.7%, BrowseComp: 92.1%, Chartography: 90.2%.

Is Claude Mythos Preview cheaper than Kimi K3.1 Pro?

Kimi K3.1 Pro is 12.5x cheaper for input tokens. Claude Mythos Preview costs $25.00/M input and $125.00/M output via anthropic. Kimi K3.1 Pro costs $2.00/M input and $10.00/M output via moonshot.

What are the context window sizes for Claude Mythos Preview and Kimi K3.1 Pro?

Claude Mythos Preview supports an unknown number of tokens and Kimi K3.1 Pro supports 1.0M 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 Preview and Kimi K3.1 Pro?

Key differences include LLM Stats Score (54.2 vs 55.5), input pricing ($25.00 vs $2.00/M), licensing (Proprietary vs Unknown). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Mythos Preview and Kimi K3.1 Pro?

Claude Mythos Preview is developed by Anthropic and Kimi K3.1 Pro is developed by Moonshot AI.

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