AI model comparison
DeepSeek V4.1 Flash vs GPT-5.6 Luna
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
DeepSeek
DeepSeek V4.1 Flash
DeepSeek V4.1 Flash is a sparse mixture-of-experts model from DeepSeek, and the first built on the company's Causal Encoder-Decoder (CED) architecture.
- Input / 1M
- $0.30
- Output / 1M
- $1.20
- Context
- 1.05M
OpenAI
GPT-5.6 Luna
GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series.
- Input / 1M
- $0.20
- Output / 1M
- $1.20
- Context
- 1.05M
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
GPT-5.6 Luna
1.2x cheaper for a typical chat
Higher intelligence score
DeepSeek V4.1 Flash
39.5 vs 37.3 on Artificial Analysis
Larger context window
GPT-5.6 Luna
1.05M vs 1.05M tokens
Newer release
DeepSeek V4.1 Flash
Released September 10, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
DeepSeek V4.1 Flash39.5GPT-5.6 Luna37.3Coding index
DeepSeek V4.1 FlashNot availableGPT-5.6 Luna71.4Agentic index
DeepSeek V4.1 FlashNot availableGPT-5.6 Luna42.1Pricing
DeepSeek V4.1 Flash vs GPT-5.6 Luna API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | DeepSeek V4.1 Flash | GPT-5.6 Luna |
|---|---|---|
| Input tokensPer 1M tokens | $0.30 | $0.20 |
| Output tokensPer 1M tokens | $1.20 | $1.20 |
| Cached input (read)Per 1M tokens | $0.01 | $0.02 |
| Cache writePer 1M tokens | Not available | $0.25 |
| Long-context pricingPer 1M tokens, for very long prompts | Same rate at any length | $0.40 in / $1.80 out above 272K |
| Web searchPer request | Not available | $0.01 |
What it costs in practice
Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.
Chat message
2K in, 500 out
DeepSeek V4.1 Flash$1.20GPT-5.6 Luna$1Coding task
30K in, 4K out
DeepSeek V4.1 Flash$13.80$4.98 cachedGPT-5.6 Luna$10.80$5.40 cachedLong document summary
150K in, 2K out
DeepSeek V4.1 Flash$47.40$3.30 cachedGPT-5.6 Luna$32.40$5.40 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | DeepSeek V4.1 Flash | GPT-5.6 Luna |
|---|---|---|
| Context window | 1.05M tokens | 1.05M tokens |
| Max output | 944K tokens | 128K tokens |
| Input types | Image, Text | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | Max, High, Low | Max, Extra high, High, Medium, Low, None |
| Default reasoning effort | High | Medium |
| Release date | September 10, 2026 | July 9, 2026 |
Features
Supported features
API features available for each model.
| Metric | DeepSeek V4.1 Flash | GPT-5.6 Luna |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Supported | Not supported |
| Stop sequences | Supported | Not supported |
| Deterministic seed | Supported | Supported |
| Verbosity control | Not supported | Supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
DeepSeek V4.1 FlashView full model details- DeepSeek V4.1 Flash vs GLM 5.3 Flash
- DeepSeek V4.1 Flash vs MiMo-V2.6-Flash
- DeepSeek V4.1 Flash vs Hy4 preview
- DeepSeek V4.1 Flash vs GPT-6 Luna
- DeepSeek V4.1 Flash vs DeepSeek V4 Flash 0731
- DeepSeek V4.1 Flash vs Claude Opus 5.5
- DeepSeek V4.1 Flash vs GLM 5.3
- DeepSeek V4.1 Flash vs DeepSeek V4 Flash 0423
- DeepSeek V4.1 Flash vs Step 5 Preview
- DeepSeek V4.1 Flash vs Gemini 3.8 Flash
- DeepSeek V4.1 Flash vs Hy3
- DeepSeek V4.1 Flash vs GPT-6.1 Sol
- DeepSeek V4.1 Flash vs Muse Spark 1.3 Contributor
- DeepSeek V4.1 Flash vs GLM 5.2
- DeepSeek V4.1 Flash vs Claude Sonnet 5.5
- DeepSeek V4.1 Flash vs MiMo-V2.6-Pro
- DeepSeek V4.1 Flash vs MiniMax M3
- DeepSeek V4.1 Flash vs DeepSeek V4 Pro 0813
- DeepSeek V4.1 Flash vs GPT-6 Astra
- DeepSeek V4.1 Flash vs Claude Opus 5
- DeepSeek V4.1 Flash vs Claude Fable 5.1
- DeepSeek V4.1 Flash vs Claude Sonnet 5
- DeepSeek V4.1 Flash vs DeepSeek V4 Pro 0423
- DeepSeek V4.1 Flash vs Muse Spark 1.3
- DeepSeek V4.1 Flash vs GPT-6 Luna Pro
- DeepSeek V4.1 Flash vs Qwen3.8 Max (0902)
- DeepSeek V4.1 Flash vs Claude Haiku 5.5
- DeepSeek V4.1 Flash vs Qwen3.8 27B
- DeepSeek V4.1 Flash vs Grok 4.6
- DeepSeek V4.1 Flash vs Ling 3.1 Flash
- DeepSeek V4.1 Flash vs GPT-5.6 Terra
- DeepSeek V4.1 Flash vs Claude Opus 4.8
- DeepSeek V4.1 Flash vs Qwen3.8 Flash
- DeepSeek V4.1 Flash vs Gemini 3.7 Flash
- DeepSeek V4.1 Flash vs Qwen3.7 Flash
- DeepSeek V4.1 Flash vs Claude Opus 4.7
- DeepSeek V4.1 Flash vs Qwen3.8 2.4T A95B
- DeepSeek V4.1 Flash vs Muse Spark 1.2
- DeepSeek V4.1 Flash vs GPT-5.4
- DeepSeek V4.1 Flash vs Grok 4.5
- DeepSeek V4.1 Flash vs GPT-5.5
- DeepSeek V4.1 Flash vs DeepSeek V4 Flash Vision Exp
- DeepSeek V4.1 Flash vs GLM 5.3 FlashX
- DeepSeek V4.1 Flash vs Gemini 3.6 Flash
- DeepSeek V4.1 Flash vs Muse Spark 1.1
- DeepSeek V4.1 Flash vs GPT-5.6 Luna Pro
GPT-5.6 LunaView full model details- GPT-5.6 Luna vs GLM 5.3 Flash
- GPT-5.6 Luna vs MiMo-V2.6-Flash
- GPT-5.6 Luna vs Hy4 preview
- GPT-5.6 Luna vs GPT-6 Luna
- GPT-5.6 Luna vs DeepSeek V4 Flash 0731
- GPT-5.6 Luna vs Gemini 3.8 Flash
- GPT-5.6 Luna vs DeepSeek V4 Pro 0813
- GPT-5.6 Luna vs Claude Haiku 5.5
- GPT-5.6 Luna vs GPT-6 Luna Pro
- GPT-5.6 Luna vs Qwen3.8 27B
- GPT-5.6 Luna vs Gemini 3.7 Flash
- GPT-5.6 Luna vs Muse Spark 1.2
- GPT-5.6 Luna vs GPT-5.5
- GPT-5.6 Luna vs DeepSeek V4 Flash Vision Exp
- GPT-5.6 Luna vs Muse Spark 1.1
- GPT-5.6 Luna vs GLM 5.3 FlashX
- GPT-5.6 Luna vs GPT-5.6 Luna Pro
Our take
GPT-5.6 Luna is 1.2x cheaper for a typical chat. DeepSeek V4.1 Flash scores higher on the Artificial Analysis Intelligence Index (39.5 vs 37.3). GPT-5.6 Luna has the larger context window (1.05M vs 1.05M tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.
FAQ
Frequently asked questions
Is DeepSeek V4.1 Flash or GPT-5.6 Luna cheaper?
GPT-5.6 Luna is cheaper for a typical chat (2K input tokens and 500 output tokens). GPT-5.6 Luna costs $0.20 per 1M input tokens and $1.20 per 1M output tokens, while DeepSeek V4.1 Flash costs $0.30 per 1M input tokens and $1.20 per 1M output tokens.
Which has a bigger context window, DeepSeek V4.1 Flash or GPT-5.6 Luna?
GPT-5.6 Luna supports up to 1.05M tokens of context, compared with 1.05M for DeepSeek V4.1 Flash.
Is DeepSeek V4.1 Flash smarter than GPT-5.6 Luna?
On the Artificial Analysis Intelligence Index, DeepSeek V4.1 Flash scores 39.5 and GPT-5.6 Luna scores 37.3, putting DeepSeek V4.1 Flash ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use DeepSeek V4.1 Flash and GPT-5.6 Luna at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see DeepSeek V4.1 Flash and GPT-5.6 Luna answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to DeepSeek V4.1 Flash and GPT-5.6 Luna at the same time. Compare the answers side by side and keep the best one.