The AI arena is free today

Open Superagent

DeepSeek-V4.1-Flash vs GPT-5.6 Luna

DeepSeek-V4.1-Flash leads the LLM Stats Score 51.8 to 45.1. DeepSeek-V4.1-Flash is 1.4x cheaper per token.

DeepSeek · OpenAI · Updated for 2026

Which is better?

DeepSeek-V4.1-Flash leads the overall LLM Stats Score 51.8 to 45.1, ranking #12 overall.

In the 8 individual benchmarks reported for both models, DeepSeek-V4.1-Flash wins 6; this is a narrower head-to-head signal than the composite indexes.

On price, DeepSeek-V4.1-Flash is roughly 1.4x 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 DeepSeek-V4.1-Flash

  • overall performance matters — it scores 51.8 and ranks #12 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 6 of 8 exact shared results
  • cost matters — it's about 1.4x cheaper per token
  • you want the most recent training data — it shipped Sep 2026
  • you need open weights you can self-host or fine-tune

Choose GPT-5.6 Luna

  • you process long inputs — it offers a 1,050,000 token context window

At a glance

The differences that matter most.

Core performance indexes
51.8
#12
45.1
#31
48.9
#17
44.2
#36
44.4
#5
36.3
#21
41.3
#4
31.7
#28
Cost, coverage & limits
Benchmark wins
6 of 8
2 of 8
Input price
$0.22 / M
$0.20 / M
Output price
$0.66 / M
$1.20 / M
Context window
1,040,000
1,050,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

5 shared
Index
DeepSeek-V4.1-Flash
GPT-5.6 Luna
35.2#43
28.8#90
29.5#31
25.0#48
35.1#2
25.9#32
34.3#13
26.0#44
21.9#3
-0.3#32
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

20 reported for DeepSeek-V4.1-Flash · 45 for GPT-5.6 Luna

8 shared

DeepSeek-V4.1-Flash outperforms in 6 benchmarks (AutomationBench, DeepSWE 1.1, ExploitGym, SEC-bench Pro, Terminal-Bench 2.1, Terminal-Bench 4.0), while GPT-5.6 Luna is better at 2 benchmarks (Agents' Last Exam, GPQA).

DeepSeek-V4.1-Flash shows notably better performance in the majority of benchmarks.

Tue Sep 15 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

DeepSeek-V4.1-Flash costs less

For input processing, DeepSeek-V4.1-Flash ($0.22/1M tokens) is 1.1x more expensive than GPT-5.6 Luna ($0.20/1M tokens).

For output processing, DeepSeek-V4.1-Flash ($0.66/1M tokens) is 1.8x cheaper than GPT-5.6 Luna ($1.20/1M tokens).

In conclusion, GPT-5.6 Luna is more expensive than DeepSeek-V4.1-Flash.*

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

Lowest available price from all providers
Tue Sep 15 2026 • llm-stats.com
DeepSeek
DeepSeek-V4.1-Flash
Input tokens$0.22
Output tokens$0.66
Best providerFireworks
OpenAI
GPT-5.6 Luna
Input tokens$0.20
Output tokens$1.20
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-V4.1-Flash's 1,040,000 tokens. DeepSeek-V4.1-Flash can generate longer responses up to 393,216 tokens, while GPT-5.6 Luna is limited to 128,000 tokens.

DeepSeek
DeepSeek-V4.1-Flash
Input1,040,000 tokens
Output393,216 tokens
OpenAI
GPT-5.6 Luna
Input1,050,000 tokens
Output128,000 tokens
Tue Sep 15 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both DeepSeek-V4.1-Flash and GPT-5.6 Luna support multimodal inputs.

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

DeepSeek-V4.1-Flash

Text
Images
Audio
Video

GPT-5.6 Luna

Text
Images
Audio
Video

License

Usage and distribution terms

DeepSeek-V4.1-Flash 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.

DeepSeek-V4.1-Flash

MIT

Open weights

GPT-5.6 Luna

Proprietary

Closed source

Release Timeline

When each model was launched

DeepSeek-V4.1-Flash was released on 2026-09-10, while GPT-5.6 Luna was released on 2026-07-09.

DeepSeek-V4.1-Flash is 2 months newer than GPT-5.6 Luna.

DeepSeek-V4.1-Flash

Sep 10, 2026

4 days ago

2mo newer
GPT-5.6 Luna

Jul 9, 2026

2 months ago

Knowledge Cutoff

When training data ends

GPT-5.6 Luna has a documented knowledge cutoff of 2026-02-16, while DeepSeek-V4.1-Flash'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-V4.1-Flash's cutoff date.

DeepSeek-V4.1-Flash

GPT-5.6 Luna

Feb 2026

Provider Availability

DeepSeek-V4.1-Flash is available from Fireworks, DeepInfra, DeepSeek, Novita. GPT-5.6 Luna is available from OpenAI.

DeepSeek-V4.1-Flash

fireworks logo
Fireworks
Input Price:Input: $0.22/1MOutput Price:Output: $0.66/1M
deepinfra logo
Deepinfra
Input Price:Input: $0.30/1MOutput Price:Output: $1.20/1M
deepseek logo
DeepSeek
Input Price:Input: $0.30/1MOutput Price:Output: $1.20/1M
novita logo
Novita
Input Price:Input: $0.30/1MOutput Price:Output: $1.20/1M

GPT-5.6 Luna

openai logo
OpenAI
Input Price:Input: $0.20/1MOutput Price:Output: $1.20/1M
* 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 DeepSeek-V4.1-Flash and GPT-5.6 Luna side-by-side, then vote on the output you prefer.

DeepSeek-V4.1-Flash
✓ Preferred
GPT-5.6 Luna
Open in Playground

FAQ

Common questions about DeepSeek-V4.1-Flash vs GPT-5.6 Luna.

Which is better, DeepSeek-V4.1-Flash or GPT-5.6 Luna?

DeepSeek-V4.1-Flash leads the LLM Stats Score 51.8 to 45.1. DeepSeek-V4.1-Flash is made by DeepSeek and GPT-5.6 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 DeepSeek-V4.1-Flash compare to GPT-5.6 Luna in benchmarks?

DeepSeek-V4.1-Flash scores CodeForces: 100.0%, GPQA: 90.9%, Terminal-Bench 2.1: 90.6%, BabyVision: 89.6%, CyberGym: 88.1%. 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-V4.1-Flash cheaper than GPT-5.6 Luna?

GPT-5.6 Luna is 1.1x cheaper for input tokens. DeepSeek-V4.1-Flash costs $0.22/M input and $0.66/M output via fireworks. GPT-5.6 Luna costs $0.20/M input and $1.20/M output via openai.

What are the context window sizes for DeepSeek-V4.1-Flash and GPT-5.6 Luna?

DeepSeek-V4.1-Flash supports 1.0M 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-V4.1-Flash and GPT-5.6 Luna?

Key differences include LLM Stats Score (51.8 vs 45.1), context window (1.0M vs 1.1M), input pricing ($0.22 vs $0.20/M), licensing (MIT vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes DeepSeek-V4.1-Flash and GPT-5.6 Luna?

DeepSeek-V4.1-Flash is developed by DeepSeek and GPT-5.6 Luna is developed by OpenAI.