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DeepSeek-V4-Flash-0731 vs Qwen3.5-397B-A17B

DeepSeek-V4-Flash-0731 significantly outperforms across most benchmarks. DeepSeek-V4-Flash-0731 is 12.0x cheaper per token.

DeepSeek · Alibaba Cloud / Qwen Team · Updated for 2026

Which is better?

DeepSeek-V4-Flash-0731 outperforms in 1 benchmarks (Toolathlon), while Qwen3.5-397B-A17B is better at 0 benchmarks. DeepSeek-V4-Flash-0731 significantly outperforms across most benchmarks.

On price, DeepSeek-V4-Flash-0731 is roughly 12.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

DeepSeek-V4-Flash-0731 also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

Based on current benchmark, pricing, and model metadata for 2026.

Choose DeepSeek-V4-Flash-0731

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • cost matters — it's about 12.0x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Jul 2026

Choose Qwen3.5-397B-A17B

  • you want predictable pricing at $0.60/M input and $3.60/M output

At a glance

The differences that matter most.

Benchmark wins
1 of 1
0 of 1
Input price
$0.09 / M
$0.60 / M
Output price
$0.18 / M
$3.60 / M
Context window
1,048,576
262,144
Released
Jul 2026
Feb 2026
License
MIT
Apache 2.0

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

DeepSeek-V4-Flash-0731 outperforms in 1 benchmarks (Toolathlon), while Qwen3.5-397B-A17B is better at 0 benchmarks.

DeepSeek-V4-Flash-0731 significantly outperforms across most benchmarks.

Wed Aug 26 2026 • llm-stats.com

Arena Performance

Playground indexes and blind preference scores

Pricing Analysis

Price comparison per million tokens

DeepSeek-V4-Flash-0731 costs less

For input processing, DeepSeek-V4-Flash-0731 ($0.09/1M tokens) is 6.7x cheaper than Qwen3.5-397B-A17B ($0.60/1M tokens).

For output processing, DeepSeek-V4-Flash-0731 ($0.18/1M tokens) is 20.0x cheaper than Qwen3.5-397B-A17B ($3.60/1M tokens).

In conclusion, Qwen3.5-397B-A17B is more expensive than DeepSeek-V4-Flash-0731.*

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

Lowest available price from all providers
Wed Aug 26 2026 • llm-stats.com
DeepSeek
DeepSeek-V4-Flash-0731
Input tokens$0.09
Output tokens$0.18
Best providerDeepinfra
Alibaba Cloud / Qwen Team
Qwen3.5-397B-A17B
Input tokens$0.60
Output tokens$3.60
Best providerNovita
Notice missing or incorrect data?Start an Issue

Model Size

Parameter count comparison

93.0B diff

Qwen3.5-397B-A17B has 93.0B more parameters than DeepSeek-V4-Flash-0731, making it 30.6% larger.

DeepSeek
DeepSeek-V4-Flash-0731
304.0Bparameters
Alibaba Cloud / Qwen Team
Qwen3.5-397B-A17B
397.0Bparameters
304.0B
DeepSeek-V4-Flash-0731
397.0B
Qwen3.5-397B-A17B

Context Window

Maximum input and output token capacity

DeepSeek-V4-Flash-0731 accepts 1,048,576 input tokens compared to Qwen3.5-397B-A17B's 262,144 tokens. DeepSeek-V4-Flash-0731 can generate longer responses up to 384,000 tokens, while Qwen3.5-397B-A17B is limited to 64,000 tokens.

DeepSeek
DeepSeek-V4-Flash-0731
Input1,048,576 tokens
Output384,000 tokens
Alibaba Cloud / Qwen Team
Qwen3.5-397B-A17B
Input262,144 tokens
Output64,000 tokens
Wed Aug 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Qwen3.5-397B-A17B supports multimodal inputs, whereas DeepSeek-V4-Flash-0731 does not.

Qwen3.5-397B-A17B can handle both text and other forms of data like images, making it suitable for multimodal applications.

DeepSeek-V4-Flash-0731

Text
Images
Audio
Video

Qwen3.5-397B-A17B

Text
Images
Audio
Video

License

Usage and distribution terms

DeepSeek-V4-Flash-0731 is licensed under MIT, while Qwen3.5-397B-A17B uses Apache 2.0.

License differences may affect how you can use these models in commercial or open-source projects.

DeepSeek-V4-Flash-0731

MIT

Open weights

Qwen3.5-397B-A17B

Apache 2.0

Open weights

Release Timeline

When each model was launched

DeepSeek-V4-Flash-0731 was released on 2026-07-31, while Qwen3.5-397B-A17B was released on 2026-02-16.

DeepSeek-V4-Flash-0731 is 6 months newer than Qwen3.5-397B-A17B.

DeepSeek-V4-Flash-0731

Jul 31, 2026

3 weeks ago

5mo newer
Qwen3.5-397B-A17B

Feb 16, 2026

6 months ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

DeepSeek-V4-Flash-0731 is available from DeepInfra, Novita, Fireworks. Qwen3.5-397B-A17B is available from Novita.

DeepSeek-V4-Flash-0731

deepinfra logo
Deepinfra
Input Price:Input: $0.09/1MOutput Price:Output: $0.18/1M
novita logo
Novita
Input Price:Input: $0.14/1MOutput Price:Output: $0.28/1M
fireworks logo
Fireworks
Input Price:Input: $0.44/1MOutput Price:Output: $1.32/1M

Qwen3.5-397B-A17B

novita logo
Novita
Input Price:Input: $0.60/1MOutput Price:Output: $3.60/1M
* 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-Flash-0731 and Qwen3.5-397B-A17B side-by-side, then vote on the output you prefer.

DeepSeek-V4-Flash-0731
✓ Preferred
Qwen3.5-397B-A17B
Open in Playground

FAQ

Common questions about DeepSeek-V4-Flash-0731 vs Qwen3.5-397B-A17B.

Which is better, DeepSeek-V4-Flash-0731 or Qwen3.5-397B-A17B?

DeepSeek-V4-Flash-0731 significantly outperforms across most benchmarks. DeepSeek-V4-Flash-0731 is made by DeepSeek and Qwen3.5-397B-A17B is made by Alibaba Cloud / Qwen Team. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does DeepSeek-V4-Flash-0731 compare to Qwen3.5-397B-A17B in benchmarks?

DeepSeek-V4-Flash-0731 scores Terminal-Bench 2.1: 82.7%, CyberGym: 76.7%, Toolathlon: 70.3%, DSBench-FullStack: 68.7%, DSBench-Hard: 59.6%. Qwen3.5-397B-A17B scores MMLU-Redux: 94.9%, HMMT 2025: 94.8%, C-Eval: 93.0%, HMMT25: 92.7%, IFEval: 92.6%.

Is DeepSeek-V4-Flash-0731 cheaper than Qwen3.5-397B-A17B?

DeepSeek-V4-Flash-0731 is 6.7x cheaper for input tokens. DeepSeek-V4-Flash-0731 costs $0.09/M input and $0.18/M output via deepinfra. Qwen3.5-397B-A17B costs $0.60/M input and $3.60/M output via novita.

What are the context window sizes for DeepSeek-V4-Flash-0731 and Qwen3.5-397B-A17B?

DeepSeek-V4-Flash-0731 supports 1.0M tokens and Qwen3.5-397B-A17B supports 262K 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-Flash-0731 and Qwen3.5-397B-A17B?

Key differences include context window (1.0M vs 262K), input pricing ($0.09 vs $0.60/M), multimodal support (no vs yes), licensing (MIT vs Apache 2.0). See the full comparison above for benchmark-by-benchmark results.

Who makes DeepSeek-V4-Flash-0731 and Qwen3.5-397B-A17B?

DeepSeek-V4-Flash-0731 is developed by DeepSeek and Qwen3.5-397B-A17B is developed by Alibaba Cloud / Qwen Team.