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Claude Sonnet 5 vs GPT-6 Luna

Claude Sonnet 5 and GPT-6 Luna are closely matched at 47.9 and 44.5 on the LLM Stats Score. GPT-6 Luna is 20.0x cheaper per token.

Anthropic · OpenAI · Updated for 2026

Which is better?

Claude Sonnet 5 and GPT-6 Luna are closely matched on the overall LLM Stats Score at 47.9 and 44.5.

The models split the 2 individual benchmarks reported for both models evenly.

On price, GPT-6 Luna is roughly 20.0x 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 Sonnet 5

  • you want predictable pricing at $2.00/M input and $10.00/M output

Choose GPT-6 Luna

  • cost matters — it's about 20.0x 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
47.9
#26
44.5
#40
47.3
#25
40.0
#58
36.1
#24
31.4
#47
31.0
#35
31.8
#30
Cost, coverage & limits
Benchmark wins
1 of 2
1 of 2
Input price
$2.00 / M
$0.10 / M
Output price
$10.00 / M
$0.50 / M
Context window
1,000,000
1,050,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Claude Sonnet 5
GPT-6 Luna
22.2#46
22.1#47
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

23 reported for Claude Sonnet 5 · 5 for GPT-6 Luna

2 shared

Claude Sonnet 5 outperforms in 1 benchmarks (FrontierCode 1.1), while GPT-6 Luna is better at 1 benchmark (DeepSWE 1.1).

Both models are evenly matched across the benchmarks.

Wed Sep 23 2026 • llm-stats.com

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 Sonnet 5 ($2.00/1M tokens) is 20.0x more expensive than GPT-6 Luna ($0.10/1M tokens).

For output processing, Claude Sonnet 5 ($10.00/1M tokens) is 20.0x more expensive than GPT-6 Luna ($0.50/1M tokens).

In conclusion, Claude Sonnet 5 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 Sonnet 5
Input tokens$2.00
Output tokens$10.00
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 Sonnet 5's 1,000,000 tokens. GPT-6 Luna can generate longer responses up to 128,000 tokens, while Claude Sonnet 5 is limited to 64,000 tokens.

Anthropic
Claude Sonnet 5
Input1,000,000 tokens
Output64,000 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 Sonnet 5 and GPT-6 Luna support multimodal inputs.

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

Claude Sonnet 5

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 Sonnet 5

Proprietary

Closed source

GPT-6 Luna

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Sonnet 5 was released on 2026-06-30, while GPT-6 Luna was released on 2026-09-22.

GPT-6 Luna is 3 months newer than Claude Sonnet 5.

Claude Sonnet 5

Jun 30, 2026

2 months ago

GPT-6 Luna

Sep 22, 2026

0 days ago

2mo newer

Knowledge Cutoff

When training data ends

GPT-6 Luna has a documented knowledge cutoff of 2026-05-18, while Claude Sonnet 5'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 Sonnet 5's cutoff date.

Claude Sonnet 5

GPT-6 Luna

May 2026

Provider Availability

Claude Sonnet 5 is available from Anthropic, DeepInfra. GPT-6 Luna is available from OpenAI.

Claude Sonnet 5

anthropic logo
Anthropic
Input Price:Input: $2.00/1MOutput Price:Output: $10.00/1M
deepinfra logo
Deepinfra
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M

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 Sonnet 5 and GPT-6 Luna side-by-side, then vote on the output you prefer.

Claude Sonnet 5
✓ Preferred
GPT-6 Luna
Open in Playground

FAQ

Common questions about Claude Sonnet 5 vs GPT-6 Luna.

Which is better, Claude Sonnet 5 or GPT-6 Luna?

Claude Sonnet 5 and GPT-6 Luna are closely matched on the LLM Stats Score at 47.9 and 44.5. Claude Sonnet 5 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 Sonnet 5 compare to GPT-6 Luna in benchmarks?

Claude Sonnet 5 scores CharXiv-R: 88.3%, ChartMuseum: 86.7%, SWE-Bench Verified: 85.2%, BrowseComp: 84.7%, GDP.pdf: 81.6%. 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 Sonnet 5 cheaper than GPT-6 Luna?

GPT-6 Luna is 20.0x cheaper for input tokens. Claude Sonnet 5 costs $2.00/M input and $10.00/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 Sonnet 5 and GPT-6 Luna?

Claude Sonnet 5 supports 1.0M 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 Sonnet 5 and GPT-6 Luna?

Key differences include LLM Stats Score (47.9 vs 44.5), context window (1.0M vs 1.1M), input pricing ($2.00 vs $0.10/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Sonnet 5 and GPT-6 Luna?

Claude Sonnet 5 is developed by Anthropic and GPT-6 Luna is developed by OpenAI.