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Qwen3.5-397B-A17B vs Step-3.5-Flash

Qwen3.5-397B-A17B and Step-3.5-Flash are closely matched at 38.7 and 37.1 on the LLM Stats Score. Step-3.5-Flash is 6.2x cheaper per token.

Alibaba Cloud / Qwen Team · StepFun · Updated for 2026

Which is better?

Qwen3.5-397B-A17B and Step-3.5-Flash are closely matched on the overall LLM Stats Score at 38.7 and 37.1.

In the 5 individual benchmarks reported for both models, Step-3.5-Flash wins 3; this is a narrower head-to-head signal than the composite indexes.

On price, Step-3.5-Flash is roughly 6.2x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Qwen3.5-397B-A17B also accepts a larger context window (262,144 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 Qwen3.5-397B-A17B

  • you process long inputs — it offers a 262,144 token context window
  • you want the most recent training data — it shipped Feb 2026

Choose Step-3.5-Flash

  • you value its reported benchmark strengths — it wins 3 of 5 exact shared results
  • cost matters — it's about 6.2x cheaper per token

At a glance

The differences that matter most.

Qwen3.5-397B-A17B
Alibaba Cloud / Qwen Team
Step-3.5-Flash
StepFun
Core performance indexes
LLM Stats Score
38.7
#70
37.1
#76
Reasoning
38.5
#69
37.2
#75
Coding
22.9
#86
20.4
#104
Agents
19.9
#70
15.3
#92
Cost, coverage & limits
Benchmark wins
2 of 5
3 of 5
Input price
$0.45 / M
$0.10 / M
Output price
$3.00 / M
$0.40 / M
Context window
262,144
65,536

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Qwen3.5-397B-A17B
Step-3.5-Flash
Math
36.6#38
33.9#52
Tool use
16.6#82
13.3#103
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

38 reported for Qwen3.5-397B-A17B · 7 for Step-3.5-Flash

5 shared

Qwen3.5-397B-A17B outperforms in 2 benchmarks (SWE-Bench Verified, Terminal-Bench 2.0), while Step-3.5-Flash is better at 2 benchmarks (IMO-AnswerBench, LiveCodeBench v6).

Both models are evenly matched across the benchmarks.

Fri Oct 02 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Step-3.5-Flash costs less

For input processing, Qwen3.5-397B-A17B ($0.45/1M tokens) is 4.5x more expensive than Step-3.5-Flash ($0.10/1M tokens).

For output processing, Qwen3.5-397B-A17B ($3.00/1M tokens) is 7.5x more expensive than Step-3.5-Flash ($0.40/1M tokens).

In conclusion, Qwen3.5-397B-A17B is more expensive than Step-3.5-Flash.*

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

Lowest available price from all providers
Fri Oct 02 2026 • llm-stats.com
Alibaba Cloud / Qwen Team
Qwen3.5-397B-A17B
Input tokens$0.45
Output tokens$3.00
Best providerDeepinfra
StepFun
Step-3.5-Flash
Input tokens$0.10
Output tokens$0.40
Best providerStepFun
Notice missing or incorrect data?

Model Size

Parameter count comparison

201.0B diff

Qwen3.5-397B-A17B has 201.0B more parameters than Step-3.5-Flash, making it 102.6% larger.

Alibaba Cloud / Qwen Team
Qwen3.5-397B-A17B
397.0Bparameters
StepFun
Step-3.5-Flash
196.0Bparameters
397.0B
Qwen3.5-397B-A17B
196.0B
Step-3.5-Flash

Context Window

Maximum input and output token capacity

Qwen3.5-397B-A17B accepts 262,144 input tokens compared to Step-3.5-Flash's 65,536 tokens. Qwen3.5-397B-A17B can generate longer responses up to 262,144 tokens, while Step-3.5-Flash is limited to 8,192 tokens.

Alibaba Cloud / Qwen Team
Qwen3.5-397B-A17B
Input262,144 tokens
Output262,144 tokens
StepFun
Step-3.5-Flash
Input65,536 tokens
Output8,192 tokens
Fri Oct 02 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Qwen3.5-397B-A17B supports multimodal inputs, whereas Step-3.5-Flash does not.

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

Qwen3.5-397B-A17B

Text
Images
Audio
Video

Step-3.5-Flash

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under Apache 2.0.

Both models share the same licensing terms, providing consistent usage rights.

Qwen3.5-397B-A17B

Apache 2.0

Open weights

Step-3.5-Flash

Apache 2.0

Open weights

Release Timeline

When each model was launched

Qwen3.5-397B-A17B was released on 2026-02-16, while Step-3.5-Flash was released on 2026-02-02.

Qwen3.5-397B-A17B is 0 month newer than Step-3.5-Flash.

Qwen3.5-397B-A17B

Feb 16, 2026

7 months ago

2w newer
Step-3.5-Flash

Feb 2, 2026

8 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

Qwen3.5-397B-A17B is available from DeepInfra, Novita. Step-3.5-Flash is available from StepFun.

Qwen3.5-397B-A17B

deepinfra logo
Deepinfra
Input Price:Input: $0.45/1MOutput Price:Output: $3.00/1M
novita logo
Novita
Input Price:Input: $0.60/1MOutput Price:Output: $3.60/1M

Step-3.5-Flash

stepfun logo
StepFun
Input Price:Input: $0.10/1MOutput Price:Output: $0.40/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Qwen3.5-397B-A17B and Step-3.5-Flash side-by-side, then vote on the output you prefer.

Qwen3.5-397B-A17B
✓ Preferred
Step-3.5-Flash
Open in Playground

FAQ

Common questions about Qwen3.5-397B-A17B vs Step-3.5-Flash.

Which is better, Qwen3.5-397B-A17B or Step-3.5-Flash?

Qwen3.5-397B-A17B and Step-3.5-Flash are closely matched on the LLM Stats Score at 38.7 and 37.1. Qwen3.5-397B-A17B is made by Alibaba Cloud / Qwen Team and Step-3.5-Flash is made by StepFun. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Qwen3.5-397B-A17B compare to Step-3.5-Flash in benchmarks?

Qwen3.5-397B-A17B scores MMLU-Redux: 94.9%, HMMT 2025: 94.8%, C-Eval: 93.0%, HMMT25: 92.7%, IFEval: 92.6%. Step-3.5-Flash scores AIME 2025: 97.3%, Tau-bench: 88.2%, LiveCodeBench v6: 86.4%, IMO-AnswerBench: 85.4%, SWE-Bench Verified: 74.4%.

Is Qwen3.5-397B-A17B cheaper than Step-3.5-Flash?

Step-3.5-Flash is 4.5x cheaper for input tokens. Qwen3.5-397B-A17B costs $0.45/M input and $3.00/M output via deepinfra. Step-3.5-Flash costs $0.10/M input and $0.40/M output via stepfun.

What are the context window sizes for Qwen3.5-397B-A17B and Step-3.5-Flash?

Qwen3.5-397B-A17B supports 262K tokens and Step-3.5-Flash supports 66K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Qwen3.5-397B-A17B and Step-3.5-Flash?

Key differences include LLM Stats Score (38.7 vs 37.1), context window (262K vs 66K), input pricing ($0.45 vs $0.10/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Qwen3.5-397B-A17B and Step-3.5-Flash?

Qwen3.5-397B-A17B is developed by Alibaba Cloud / Qwen Team and Step-3.5-Flash is developed by StepFun.

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