DeepSeek
DeepSeek V4.1 Flash
A new Flash generation for coding and long-context agent work. DeepSeek's asymmetric architecture uses 8B active parameters to read input and 16B to generate output.
Replaces DeepSeek V4 Flash 0731: input $0.0798 → $0.0788 per 1M (-1%), output $0.1607 → $0.315 per 1M (+96%), context 1M → 1M, max output 384K → 33K.
Run this model
deepseek/deepseek-v4.1-flash
Use an endpoint supported by this model.
Get a key for this setup →const response = await fetch('https://api.minirouter.sh/v1/chat/completions', { method: 'POST', headers: { Authorization: `Bearer ${process.env.MINIROUTER_KEY}`, 'Content-Type': 'application/json', }, body: JSON.stringify({ model: 'deepseek/deepseek-v4.1-flash', messages: [{ role: 'user', content: 'Why is the sky blue?' }], max_tokens: 1024, }),}) const data = await response.json()console.log(data.choices[0].message.content)Use deepseek/deepseek-v4.1-flash for text and image input. Start with the Chat Completions example; publisher client integrations do not establish MiniRouter client compatibility.
Text and image input with provider peak-hour pricingMiniRouter supports text and image input for this model. Prices shown include MiniRouter's markup. Final charges reflect Vercel's reported usage and any peak-hour surcharge. Source ↗
Model overview
- Input / 1M
- $0.07875
- All-in MiniRouter rate
- Output / 1M
- $0.315
- All-in MiniRouter rate
- Context
- 1M
- 1,048,576 tokens
- Max output
- 33K
- tokens
- Architecture
- 552B MoE
- 8B input / 16B output active
- DeepSWE v1.1
- 74.2%
- DeepSeek-reported, max effort
- Announced
- 10 Sept 2026
- publisher release
A step forward for coding agents.
DeepSeek reports 74.2% on DeepSWE v1.1 and 90.6% on Terminal Bench 2.1. The comparisons below come from one publisher table, with separate axes for each benchmark.
These evaluations use maximum effort (100), temperature 1.0 and top_p 0.95. Terminal Bench uses DeepSeek Harness Minimal; DeepSWE uses mini-SWE, with a 1M-token context. They are not MiniRouter performance measurements.
V4.1 vs V4
DeepSWE v1.1
Resolved repository tasks rise from 54.4% for V4 Flash and 62.7% for V4 Pro to 74.2%.
DeepSeek-reported results
0 to 100%
- V4.1 Flash74.2%
- V4 Pro62.7%
- V4 Flash54.4%
View chart data
| Model | Reported result |
|---|---|
| V4.1 Flash | 74.2% |
| V4 Pro | 62.7% |
| V4 Flash | 54.4% |
V4.1 vs V4
Terminal Bench 2.1
Terminal task Pass@1 rises from 82.7% for V4 Flash and 87.9% for V4 Pro to 90.6%.
DeepSeek-reported results
0 to 100%
- V4.1 Flash90.6%
- V4 Pro87.9%
- V4 Flash82.7%
View chart data
| Model | Reported result |
|---|---|
| V4.1 Flash | 90.6% |
| V4 Pro | 87.9% |
| V4 Flash | 82.7% |
Evaluate it on the work you repeat.
- [ 01 ]
Repository work and terminal tasks
Try it on bounded fixes, code review, and tool-driven development. The published DeepSWE and Terminal Bench results make these useful starting points for your own evaluation.
- [ 02 ]
Long documents and repeated context
Use the live context and output limits shown above. Repeated context may benefit from upstream caching; actual cache use and peak hours affect the final bill.
- [ 03 ]
Check reasoning and visual requirements
The publisher reports GPQA Diamond at 90.9%, below V4 Pro's 92.4% in its table. The model also accepts images on MiniRouter.
Plan around peak hours and output tokens.
- [ 01 ]
Separate list prices from your route price
DeepSeek lists $0.15/M uncached input and $0.60/M output off-peak, before MiniRouter's markup. Peak list prices are $0.30/M and $1.20/M respectively.
- [ 02 ]
Compare the whole task
Reasoning and longer answers can increase output usage. Compare total task cost and success rate with V4 Flash or another coding model using the same tools and prompt.
Use the permanent model ID.
- [ 01 ]
Replace the beta ID
Change deepseek/deepseek-v4.1-flash-beta to deepseek/deepseek-v4.1-flash once the permanent model appears in MiniRouter's catalog. Keep your MiniRouter base URL and key.
- [ 02 ]
Check aliases at the provider boundary
DeepSeek's direct API uses deepseek-flash and redirects older V4 aliases. Those publisher redirects do not guarantee that a MiniRouter V4 ID selects this release.
- [ 03 ]
Keep evaluation results separate
The September 10 Artificial Analysis API refresh has no matching V4.1 Flash evaluation. Use the publisher results above as evidence to investigate; independent speed and quality measurements are not yet included here.
One route, standard clients.
https://api.minirouter.sh/v1deepseek/deepseek-v4.1-flash/v1/chat/completions/v1/messages/v1/responsesConfigured providers. Priority follows the live catalog order.
| Provider | Priority | Input / 1M | Output / 1M | Parameters | Access |
|---|---|---|---|---|---|
vercel | 1 | $0.07875 | $0.315 | max_tokens, temperature, stop, tools, tool_choice, reasoning, include_reasoning, response_format, structured_outputs | MiniRouter balance |