Model Comparison
DeepSeek-V4-Flash-Max vs GPT-5.6 LunaWhich is better in 2026?
GPT-5.6 Luna significantly outperforms across most benchmarks. DeepSeek-V4-Flash-Max is 18.0x cheaper per token.
Verdict: DeepSeek-V4-Flash-Max vs GPT-5.6 Luna — which is better?
DeepSeek-V4-Flash-Max (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-V4-Flash-Max outperforms in 0 benchmarks, while GPT-5.6 Luna is better at 5 benchmarks (BrowseComp, GDPval-AA, GPQA, SWE-Bench Pro, Toolathlon). GPT-5.6 Luna significantly outperforms across most benchmarks.
On price, DeepSeek-V4-Flash-Max is roughly 18.0x 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-V4-Flash-Max if…
- cost matters — it's about 18.0x 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 5 of 5 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
DeepSeek-V4-Flash-Max outperforms in 0 benchmarks, while GPT-5.6 Luna is better at 5 benchmarks (BrowseComp, GDPval-AA, GPQA, SWE-Bench Pro, Toolathlon).
GPT-5.6 Luna significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, DeepSeek-V4-Flash-Max ($0.10/1M tokens) is 10.0x cheaper than GPT-5.6 Luna ($1.00/1M tokens).
For output processing, DeepSeek-V4-Flash-Max ($0.20/1M tokens) is 30.0x cheaper than GPT-5.6 Luna ($6.00/1M tokens).
In conclusion, GPT-5.6 Luna is more expensive than DeepSeek-V4-Flash-Max.*
* 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 DeepSeek-V4-Flash-Max's 1,048,576 tokens. GPT-5.6 Luna can generate longer responses up to 128,000 tokens, while DeepSeek-V4-Flash-Max is limited to 65,536 tokens.
Input Capabilities
Supported data types and modalities
GPT-5.6 Luna supports multimodal inputs, whereas DeepSeek-V4-Flash-Max does not.
GPT-5.6 Luna can handle both text and other forms of data like images, making it suitable for multimodal applications.
DeepSeek-V4-Flash-Max
GPT-5.6 Luna
License
Usage and distribution terms
DeepSeek-V4-Flash-Max is licensed under MIT, 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.
MIT
Open weights
Proprietary
Closed source
Release Timeline
When each model was launched
DeepSeek-V4-Flash-Max was released on 2026-04-23, while GPT-5.6 Luna was released on 2026-07-09.
GPT-5.6 Luna is 3 months newer than DeepSeek-V4-Flash-Max.
Apr 23, 2026
2 months ago
Jul 9, 2026
1 weeks ago
2mo newerKnowledge Cutoff
When training data ends
GPT-5.6 Luna has a documented knowledge cutoff of 2026-02-16, while DeepSeek-V4-Flash-Max'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-V4-Flash-Max's cutoff date.
—
Feb 2026
Provider Availability
DeepSeek-V4-Flash-Max is available from DeepInfra, DeepSeek, Fireworks, Novita. GPT-5.6 Luna is available from OpenAI.
DeepSeek-V4-Flash-Max
GPT-5.6 Luna
Outputs Comparison
Key Takeaways
GPT-5.6 Luna
View detailsOpenAI
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against DeepSeek-V4-Flash-Max and GPT-5.6 Luna side-by-side, then vote on the output you prefer.
| Feature | | |
|---|
FAQ
Common questions about DeepSeek-V4-Flash-Max vs GPT-5.6 Luna.