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Model comparison · Updated 10 Oct 2026

DeepSeek V4.1 Flash vs Qwen3.5 Plus 2026-04-20

DeepSeek V4.1 Flash and Qwen3.5 Plus 2026-04-20 cost the same on input, $0.30 per 1M tokens. DeepSeek V4.1 Flash has the larger context window (1.05M against 1M tokens). For a support chatbot at 10,000 chats a day, the standard-tier bill is about $243 a month for DeepSeek V4.1 Flash and $297 for Qwen3.5 Plus 2026-04-20.

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ModelsAtlas. “DeepSeek V4.1 Flash vs Qwen3.5 Plus 2026-04-20”. Retrieved 10 Oct 2026. https://modelsatlas.com/compare/deepseek/v4-1/vs/qwen/3-5-plus

Model A

DeepSeek V4.1 Flash

by DeepSeek · weights not marked open · GRIDD5

Input / 1M
$0.30
observed We measured
Source
Our catalogue
Retrieved
10 Oct 2026
Output / 1M$1.20
Context1.05M
vs

Model B

Qwen3.5 Plus 2026-04-20

by Qwen (Alibaba) · weights not marked open · GRIDD5

Input / 1M
$0.30
observed We measured
Source
Our catalogue
Retrieved
17 Aug 2026
Output / 1M$1.80
Context1M

Key numbers

Standard tier · highlighted = better

DeepSeek V4.1 Flash
Qwen3.5 Plus 2026-04-20
Input / 1M tokens
$0.30
$0.30
Output / 1M tokens
$1.20
$1.80
Batch input / output
$0.11 / $0.34
Not listed
Context window
1,048,576
1,000,000
Input types
Not disclosed
Not disclosed
Weights
Not marked open
Not marked open
Tiers listed
batch, standard
standard
Prices checked
2026-10-10
2026-09-01

What it costs for real workloads

Monthly, standard tier, 30 days

Support chatbot10k chats/day · 1.5k in, 300 out
$243/mo
$297/mo
RAG over documents2k queries/day · 12k in, 500 out
$252/mo
$270/mo
Coding agent300 tasks/day · 60k in, 8k out
$248/mo
$292/mo

DeepSeek V4.1 Flash   Qwen3.5 Plus 2026-04-20 · Derived from the standard-tier prices above, input and output tokens per request as stated, 30 days. Excludes caching discounts and batch. Try your own numbers.

On the atlas

Price band (A–H) × context band (1–6)

Same square. DeepSeek V4.1 Flash and Qwen3.5 Plus 2026-04-20 share D5.

Same square as DeepSeek V4.1 Flash: Gemini 2.5 Flash ($0.30), Gemini 3.5 Flash Lite ($0.30), MiniMax M3 ($0.30). Open D5

AFreeB<$0.10C$0.10–0.30D$0.30–1E$1–3F$3–10G$10–30H$30+1<32K232–128K3128–256K4256K–1M51M6>1MINPUT PRICE PER 1M TOKENS →CONTEXT WINDOW ↑ · position within a square follows the real valueGemini 2.5 Flash · D5Gemini 3.5 Flash Lite · D5MiniMax M3 · D5Qwen3.7 Plus · D5Qwen3.6 Plus · D5DeepSeek V4.1 FlashDeepSeek V4.1 FlashQwen3.5 Plus 2026-04-20Qwen3.5 Plus 2026-04-20
DeepSeek V4.1 FlashQwen3.5 Plus 2026-04-20Nearest neighboursOpen weights
View the map as a table (1 squares)
SquarePrice bandContext bandModels
GRIDD5$0.30–11MDeepSeek V4.1 Flash, Qwen3.5 Plus 2026-04-20, Gemini 2.5 Flash, Gemini 3.5 Flash Lite, MiniMax M3, Qwen3.7 Plus, Qwen3.6 Plus

Capabilities side by side

Only what our records list

DeepSeek V4.1 Flash
Qwen3.5 Plus 2026-04-20
Vision input
Not disclosed
Not disclosed
Audio input
Not disclosed
Not disclosed
Open weights
Not marked open
Not marked open
Batch tier
Supported
Not listed
Free tier
Not listed
Not listed
Thinking tier
Not listed
Not listed

Neither record lists input types, so we do not claim any.

Which should you choose?

Editorial

Choose DeepSeek V4.1 Flash if…

  • output dominates your bill: $1.20 per 1M output against $1.80
  • your prompts are long: it takes 1,048,576 tokens against 1,000,000
  • work can wait: it lists a batch tier and the other does not

Choose Qwen3.5 Plus 2026-04-20 if…

Nothing in the recorded numbers favours Qwen3.5 Plus 2026-04-20 over DeepSeek V4.1 Flash. Pick it for what our records do not cover — your own tests, or an account you already have with Qwen (Alibaba).

Each reason is a fact from the tables above. Picking between them is our judgement, and we do not benchmark quality: price and context are what we can measure, so test both on your own prompts before you commit.

Questions

Is DeepSeek V4.1 Flash better than Qwen3.5 Plus 2026-04-20?
We do not benchmark quality, so we cannot say. On the recorded numbers: DeepSeek V4.1 Flash and Qwen3.5 Plus 2026-04-20 cost the same on input, $0.30 per 1M tokens. DeepSeek V4.1 Flash has the larger context window (1.05M against 1M tokens). For a support chatbot at 10,000 chats a day, the standard-tier bill is about $243 a month for DeepSeek V4.1 Flash and $297 for Qwen3.5 Plus 2026-04-20. Which is better for you depends on your task; test both on your own prompts.
Which is cheaper, DeepSeek V4.1 Flash or Qwen3.5 Plus 2026-04-20?
They cost the same on input, $0.30 per 1M tokens. Output is $1.20 for DeepSeek V4.1 Flash and $1.80 for Qwen3.5 Plus 2026-04-20.
How much does each cost per 1M tokens?
DeepSeek V4.1 Flash: $0.30 input and $1.20 output. Qwen3.5 Plus 2026-04-20: $0.30 input and $1.80 output. Standard tier, USD.
Which has the larger context window?
DeepSeek V4.1 Flash, with 1,048,576 tokens. Qwen3.5 Plus 2026-04-20 has 1,000,000 tokens.
Do both offer batch pricing?
DeepSeek V4.1 Flash lists a batch tier, at 37% of its standard price. Qwen3.5 Plus 2026-04-20 lists no batch tier.
Can both read images or audio?
Input types recorded for DeepSeek V4.1 Flash: none recorded. For Qwen3.5 Plus 2026-04-20: none recorded. Where a record lists none we say so rather than guess; check each vendor's documentation before relying on a capability.
Is either model open-weight?
DeepSeek V4.1 Flash: not marked open-weight in our records. Qwen3.5 Plus 2026-04-20: not marked open-weight in our records.
What would each cost for a support chatbot?
At 10,000 chats a day, 1,500 input and 300 output tokens each, 30 days, standard tier: about $243 a month for DeepSeek V4.1 Flash and $297 for Qwen3.5 Plus 2026-04-20. This is our calculation from the listed prices, not a quote.

About the two models

DeepSeek V4.1 Flash

By DeepSeek. $0.30 input and $1.20 output per 1M tokens, 1.05M context, atlas square D5. Tiers listed: batch, standard.

Full specs & pricing →

Qwen3.5 Plus 2026-04-20

By Qwen (Alibaba). $0.30 input and $1.80 output per 1M tokens, 1M context, atlas square D5. Tiers listed: standard.

Full specs & pricing →

Compare DeepSeek V4.1 Flash with…

Compare Qwen3.5 Plus 2026-04-20 with…

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