Claude Sonnet 5 vs GPT-5.6 Luna
Claude Sonnet 5 and GPT-5.6 Luna are closely matched at 48.4 and 45.3 on the LLM Stats Score. GPT-5.6 Luna is 8.9x cheaper per token.
Anthropic · OpenAI · Updated for 2026
Which is better?
Claude Sonnet 5 and GPT-5.6 Luna are closely matched on the overall LLM Stats Score at 48.4 and 45.3.
In the 10 individual benchmarks reported for both models, Claude Sonnet 5 wins 6; this is a narrower head-to-head signal than the composite indexes.
On price, GPT-5.6 Luna is roughly 8.9x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.6 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 value its reported benchmark strengths — it wins 6 of 10 exact shared results
Choose GPT-5.6 Luna
- cost matters — it's about 8.9x 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 Jul 2026
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
23 reported for Claude Sonnet 5 · 45 for GPT-5.6 Luna
Claude Sonnet 5 outperforms in 6 benchmarks (BrowseComp, FrontierCode 1.1, GDP.pdf, HealthBench Professional, SWE-Bench Pro, Toolathlon), while GPT-5.6 Luna is better at 4 benchmarks (AutomationBench, BenchCAD, DeepSWE 1.1, Terminal-Bench 4.0).
Claude Sonnet 5 has a slight edge in benchmark performance.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Sonnet 5 ($2.00/1M tokens) is 10.0x more expensive than GPT-5.6 Luna ($0.20/1M tokens).
For output processing, Claude Sonnet 5 ($10.00/1M tokens) is 8.3x more expensive than GPT-5.6 Luna ($1.20/1M tokens).
In conclusion, Claude Sonnet 5 is more expensive than GPT-5.6 Luna.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.6 Luna accepts 1,050,000 input tokens compared to Claude Sonnet 5's 1,000,000 tokens. GPT-5.6 Luna can generate longer responses up to 128,000 tokens, while Claude Sonnet 5 is limited to 64,000 tokens.
Input capabilities
Documented input modalities across available providers
Both Claude Sonnet 5 and GPT-5.6 Luna support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude Sonnet 5
GPT-5.6 Luna
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Claude Sonnet 5 was released on 2026-06-30, while GPT-5.6 Luna was released on 2026-07-09.
GPT-5.6 Luna is 0 month newer than Claude Sonnet 5.
Jun 30, 2026
2 months ago
Jul 9, 2026
2 months ago
1w newerKnowledge Cutoff
When training data ends
GPT-5.6 Luna has a documented knowledge cutoff of 2026-02-16, while Claude Sonnet 5's cutoff date is not specified.
We can confirm GPT-5.6 Luna's training data extends to 2026-02-16, but cannot make a direct comparison without Claude Sonnet 5's cutoff date.
—
Feb 2026
Provider Availability
Claude Sonnet 5 is available from Anthropic, DeepInfra. GPT-5.6 Luna is available from OpenAI.
Claude Sonnet 5
GPT-5.6 Luna
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Sonnet 5 and GPT-5.6 Luna side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Sonnet 5 vs GPT-5.6 Luna.