Model Comparison

DeepSeek-V3 vs GPT-5.6 LunaWhich is better in 2026?

GPT-5.6 Luna significantly outperforms across most benchmarks. DeepSeek-V3 is 4.7x cheaper per token.

Verdict: DeepSeek-V3 vs GPT-5.6 Luna — which is better?

DeepSeek-V3 (by DeepSeek) and GPT-5.6 Luna (by OpenAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

DeepSeek-V3 outperforms in 0 benchmarks, while GPT-5.6 Luna is better at 1 benchmark (GPQA). GPT-5.6 Luna significantly outperforms across most benchmarks.

On price, DeepSeek-V3 is roughly 4.7x 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.

Choose DeepSeek-V3 if…

  • cost matters — it's about 4.7x cheaper per token
  • you need open weights you can self-host or fine-tune

Choose GPT-5.6 Luna if…

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • you process long inputs — it offers a 1,050,000 token context window
  • you want the most recent training data — it shipped Jul 2026

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

DeepSeek-V3 outperforms in 0 benchmarks, while GPT-5.6 Luna is better at 1 benchmark (GPQA).

GPT-5.6 Luna significantly outperforms across most benchmarks.

Sat Jul 18 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

DeepSeek-V3 costs less

For input processing, DeepSeek-V3 ($0.27/1M tokens) is 3.7x cheaper than GPT-5.6 Luna ($1.00/1M tokens).

For output processing, DeepSeek-V3 ($1.10/1M tokens) is 5.5x cheaper than GPT-5.6 Luna ($6.00/1M tokens).

In conclusion, GPT-5.6 Luna is more expensive than DeepSeek-V3.*

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

Lowest available price from all providers
Sat Jul 18 2026 • llm-stats.com
DeepSeek
DeepSeek-V3
Input tokens$0.27
Output tokens$1.10
Best providerDeepSeek
OpenAI
GPT-5.6 Luna
Input tokens$1.00
Output tokens$6.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5.6 Luna accepts 1,050,000 input tokens compared to DeepSeek-V3's 131,072 tokens. DeepSeek-V3 can generate longer responses up to 131,072 tokens, while GPT-5.6 Luna is limited to 128,000 tokens.

DeepSeek
DeepSeek-V3
Input131,072 tokens
Output131,072 tokens
OpenAI
GPT-5.6 Luna
Input1,050,000 tokens
Output128,000 tokens
Sat Jul 18 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

GPT-5.6 Luna supports multimodal inputs, whereas DeepSeek-V3 does not.

GPT-5.6 Luna can handle both text and other forms of data like images, making it suitable for multimodal applications.

DeepSeek-V3

Text
Images
Audio
Video

GPT-5.6 Luna

Text
Images
Audio
Video

License

Usage and distribution terms

DeepSeek-V3 is licensed under MIT + Model License (Commercial use allowed), while GPT-5.6 Luna uses a proprietary license.

License differences may affect how you can use these models in commercial or open-source projects.

DeepSeek-V3

MIT + Model License (Commercial use allowed)

Open weights

GPT-5.6 Luna

Proprietary

Closed source

Release Timeline

When each model was launched

DeepSeek-V3 was released on 2024-12-25, while GPT-5.6 Luna was released on 2026-07-09.

GPT-5.6 Luna is 19 months newer than DeepSeek-V3.

DeepSeek-V3

Dec 25, 2024

1.6 years ago

GPT-5.6 Luna

Jul 9, 2026

1 weeks ago

1.5yr newer

Knowledge Cutoff

When training data ends

GPT-5.6 Luna has a documented knowledge cutoff of 2026-02-16, while DeepSeek-V3'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 DeepSeek-V3's cutoff date.

DeepSeek-V3

—

GPT-5.6 Luna

Feb 2026

Provider Availability

DeepSeek-V3 is available from DeepSeek. GPT-5.6 Luna is available from OpenAI.

DeepSeek-V3

deepseek logo
DeepSeek
Input Price:Input: $0.27/1MOutput Price:Output: $1.10/1M

GPT-5.6 Luna

openai logo
OpenAI
Input Price:Input: $1.00/1MOutput Price:Output: $6.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

DeepSeek
Less expensive input tokens
Less expensive output tokens
Has open weights
OpenAI
Larger context window (1,050,000 tokens)
Supports multimodal inputs
Higher GPQA score (92.3% vs 59.1%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against DeepSeek-V3 and GPT-5.6 Luna side-by-side, then vote on the output you prefer.

DeepSeek-V3
✓ Preferred
GPT-5.6 Luna
Open in Playground
AI Model Comparison Table
Feature
DeepSeek
DeepSeek-V3
OpenAI
GPT-5.6 Luna

FAQ

Common questions about DeepSeek-V3 vs GPT-5.6 Luna.

Which is better, DeepSeek-V3 or GPT-5.6 Luna?

GPT-5.6 Luna significantly outperforms across most benchmarks. DeepSeek-V3 is made by DeepSeek and GPT-5.6 Luna is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does DeepSeek-V3 compare to GPT-5.6 Luna in benchmarks?

DeepSeek-V3 scores DROP: 91.6%, CLUEWSC: 90.9%, MATH-500: 90.2%, MMLU-Redux: 89.1%, MMLU: 88.5%. GPT-5.6 Luna scores Connectors: 99.9%, HealthBench Consensus: 95.1%, GPQA: 92.3%, Search and Function-Calling: 89.7%, Capture-the-Flag Challenges (Internal): 85.2%.

Is DeepSeek-V3 cheaper than GPT-5.6 Luna?

DeepSeek-V3 is 3.7x cheaper for input tokens. DeepSeek-V3 costs $0.27/M input and $1.10/M output via deepseek. GPT-5.6 Luna costs $1.00/M input and $6.00/M output via openai.

What are the context window sizes for DeepSeek-V3 and GPT-5.6 Luna?

DeepSeek-V3 supports 131K tokens and GPT-5.6 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 DeepSeek-V3 and GPT-5.6 Luna?

Key differences include context window (131K vs 1.1M), input pricing ($0.27 vs $1.00/M), multimodal support (no vs yes), licensing (MIT + Model License (Commercial use allowed) vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes DeepSeek-V3 and GPT-5.6 Luna?

DeepSeek-V3 is developed by DeepSeek and GPT-5.6 Luna is developed by OpenAI.

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