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Claude Opus 4 vs GPT-6 Luna

GPT-6 Luna leads the LLM Stats Score 44.5 to 27.7. GPT-6 Luna is 150.0x cheaper per token.

Anthropic · OpenAI · Updated for 2026

Which is better?

GPT-6 Luna leads the overall LLM Stats Score 44.5 to 27.7, ranking #41 overall.

On price, GPT-6 Luna is roughly 150.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-6 Luna also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.

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

Choose Claude Opus 4

  • you want predictable pricing at $15.00/M input and $75.00/M output

Choose GPT-6 Luna

  • overall performance matters — it scores 44.5 and ranks #41 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • cost matters — it's about 150.0x cheaper per token
  • you process long inputs — it offers a 1,050,000 token context window
  • you want the most recent training data — it shipped Sep 2026

At a glance

The differences that matter most.

Core performance indexes
27.7
#145
44.5
#41
27.7
#138
40.0
#58
17.4
#126
31.4
#47
8.2
#139
31.8
#30
Cost, coverage & limits
Benchmark wins
Input price
$15.00 / M
$0.10 / M
Output price
$75.00 / M
$0.50 / M
Context window
200,000
1,050,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Claude Opus 4
GPT-6 Luna
19.2#60
22.1#47
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

9 reported for Claude Opus 4 · 5 for GPT-6 Luna

No common benchmarks found

Claude Opus 4 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 Opus 4 ($15.00/1M tokens) is 150.0x more expensive than GPT-6 Luna ($0.10/1M tokens).

For output processing, Claude Opus 4 ($75.00/1M tokens) is 150.0x more expensive than GPT-6 Luna ($0.50/1M tokens).

In conclusion, Claude Opus 4 is more expensive than GPT-6 Luna.*

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

Lowest available price from all providers
Tue Sep 22 2026 • llm-stats.com
Anthropic
Claude Opus 4
Input tokens$15.00
Output tokens$75.00
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

GPT-6 Luna accepts 1,050,000 input tokens compared to Claude Opus 4's 200,000 tokens. GPT-6 Luna can generate longer responses up to 128,000 tokens, while Claude Opus 4 is limited to 32,000 tokens.

Anthropic
Claude Opus 4
Input200,000 tokens
Output32,000 tokens
OpenAI
GPT-6 Luna
Input1,050,000 tokens
Output128,000 tokens
Tue Sep 22 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Opus 4 and GPT-6 Luna support multimodal inputs.

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

Claude Opus 4

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 Opus 4

Proprietary

Closed source

GPT-6 Luna

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 4 was released on 2025-05-22, while GPT-6 Luna was released on 2026-09-22.

GPT-6 Luna is 16 months newer than Claude Opus 4.

Claude Opus 4

May 22, 2025

1.3 years ago

GPT-6 Luna

Sep 22, 2026

0 days ago

1.3yr newer

Knowledge Cutoff

When training data ends

GPT-6 Luna has a documented knowledge cutoff of 2026-05-18, while Claude Opus 4'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 Opus 4's cutoff date.

Claude Opus 4

GPT-6 Luna

May 2026

Provider Availability

Claude Opus 4 is available from Anthropic, Bedrock, Google. GPT-6 Luna is available from OpenAI.

Claude Opus 4

anthropic logo
Anthropic
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M
bedrock logo
AWS Bedrock
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M
google logo
Google
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M

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 Opus 4 and GPT-6 Luna side-by-side, then vote on the output you prefer.

Claude Opus 4
✓ Preferred
GPT-6 Luna
Open in Playground

FAQ

Common questions about Claude Opus 4 vs GPT-6 Luna.

Which is better, Claude Opus 4 or GPT-6 Luna?

GPT-6 Luna leads the LLM Stats Score 44.5 to 27.7. Claude Opus 4 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 Opus 4 compare to GPT-6 Luna in benchmarks?

Claude Opus 4 scores MMMLU: 88.8%, TAU-bench Retail: 81.4%, GPQA: 79.6%, MMMU (validation): 76.5%, AIME 2025: 75.5%. 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 Opus 4 cheaper than GPT-6 Luna?

GPT-6 Luna is 150.0x cheaper for input tokens. Claude Opus 4 costs $15.00/M input and $75.00/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 Opus 4 and GPT-6 Luna?

Claude Opus 4 supports 200K 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 Opus 4 and GPT-6 Luna?

Key differences include LLM Stats Score (27.7 vs 44.5), context window (200K vs 1.1M), input pricing ($15.00 vs $0.10/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 4 and GPT-6 Luna?

Claude Opus 4 is developed by Anthropic and GPT-6 Luna is developed by OpenAI.