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Claude Mythos Preview vs GPT-6 Luna

Claude Mythos Preview leads the LLM Stats Score 54.3 to 44.5. GPT-6 Luna is 250.0x cheaper per token.

Anthropic · OpenAI · Updated for 2026

Which is better?

Claude Mythos Preview leads the overall LLM Stats Score 54.3 to 44.5, ranking #6 overall.

On price, GPT-6 Luna is roughly 250.0x 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

  • overall performance matters — it scores 54.3 and ranks #6 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes

Choose GPT-6 Luna

  • cost matters — it's about 250.0x cheaper per token

At a glance

The differences that matter most.

Claude Mythos Preview
Anthropic
GPT-6 Luna
OpenAI
Core performance indexes
LLM Stats Score
54.3
#6
44.5
#41
Reasoning
55.2
#3
40.0
#58
Coding
43.7
#5
31.4
#47
Agents
35.7
#20
31.8
#30
Cost, coverage & limits
Benchmark wins
—
—
Input price
$25.00 / M
$0.10 / M
Output price
$125.00 / M
$0.50 / M
Context window
—
1,050,000

Individual benchmarks

16 reported for Claude Mythos Preview · 5 for GPT-6 Luna

No common benchmarks found

Claude Mythos Preview and GPT-6 Lunadon'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

Pricing Analysis

Price comparison per million tokens

GPT-6 Luna costs less

For input processing, Claude Mythos Preview ($25.00/1M tokens) is 250.0x more expensive than GPT-6 Luna ($0.10/1M tokens).

For output processing, Claude Mythos Preview ($125.00/1M tokens) is 250.0x more expensive than GPT-6 Luna ($0.50/1M tokens).

In conclusion, Claude Mythos Preview is more expensive than GPT-6 Luna.*

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

Lowest available price from all providers
Wed Sep 23 2026 • llm-stats.com
Anthropic
Claude Mythos Preview
Input tokens$25.00
Output tokens$125.00
Best providerAnthropic
OpenAI
GPT-6 Luna
Input tokens$0.10
Output tokens$0.50
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Only GPT-6 Luna specifies input context (1,050,000 tokens). Only GPT-6 Luna specifies output context (128,000 tokens).

Anthropic
Claude Mythos Preview
Input- tokens
Output- tokens
OpenAI
GPT-6 Luna
Input1,050,000 tokens
Output128,000 tokens
Wed Sep 23 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Mythos Preview and GPT-6 Luna support multimodal inputs.

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

Claude Mythos Preview

Text
Images
Audio
Video

GPT-6 Luna

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 Preview

Proprietary

Closed source

GPT-6 Luna

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-6 Luna was released on 2026-09-22, while Claude Mythos Preview's release date is not specified.

We can confirm GPT-6 Luna's release timeline, but cannot make a direct age comparison without Claude Mythos Preview's release date.

Claude Mythos Preview

—

GPT-6 Luna

Sep 22, 2026

0 days ago

Knowledge Cutoff

When training data ends

GPT-6 Luna has a documented knowledge cutoff of 2026-05-18, while Claude Mythos Preview's cutoff date is not specified.

We can confirm GPT-6 Luna's training data extends to 2026-05-18, but cannot make a direct comparison without Claude Mythos Preview's cutoff date.

Claude Mythos Preview

—

GPT-6 Luna

May 2026

Provider Availability

Claude Mythos Preview is available from Anthropic. GPT-6 Luna is available from OpenAI.

Claude Mythos Preview

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

GPT-6 Luna

openai logo
OpenAI
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Claude Mythos Preview and GPT-6 Luna side-by-side, then vote on the output you prefer.

Claude Mythos Preview
✓ Preferred
GPT-6 Luna
Open in Playground

FAQ

Common questions about Claude Mythos Preview vs GPT-6 Luna.

Which is better, Claude Mythos Preview or GPT-6 Luna?

Claude Mythos Preview leads the LLM Stats Score 54.3 to 44.5. Claude Mythos Preview is made by Anthropic and GPT-6 Luna is made by OpenAI. 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 GPT-6 Luna in benchmarks?

Claude Mythos Preview scores CyBench: 100.0%, USAMO25: 97.6%, GPQA: 94.6%, SWE-Bench Verified: 93.9%, CharXiv-R: 93.2%. GPT-6 Luna scores DeepSWE 1.1: 66.6%, OSWorld 2.0: 52.7%, Agents' Last Exam: 50.9%, FrontierCode 1.1: 42.4%, AutomationBench v1.0.6: 20.7%.

Is Claude Mythos Preview cheaper than GPT-6 Luna?

GPT-6 Luna is 250.0x cheaper for input tokens. Claude Mythos Preview costs $25.00/M input and $125.00/M output via anthropic. GPT-6 Luna costs $0.10/M input and $0.50/M output via openai.

What are the context window sizes for Claude Mythos Preview and GPT-6 Luna?

Claude Mythos Preview supports an unknown number of tokens and GPT-6 Luna supports 1.1M 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 GPT-6 Luna?

Key differences include LLM Stats Score (54.3 vs 44.5), input pricing ($25.00 vs $0.10/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Mythos Preview and GPT-6 Luna?

Claude Mythos Preview is developed by Anthropic and GPT-6 Luna is developed by OpenAI.

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