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Qwen3.8-27B vs Seed 2.1 Pro

Qwen3.8-27B and Seed 2.1 Pro are closely matched at 45.2 and 46.4 on the LLM Stats Score.

Alibaba Cloud / Qwen Team · ByteDance · Updated for 2026

Which is better?

Qwen3.8-27B and Seed 2.1 Pro are closely matched on the overall LLM Stats Score at 45.2 and 46.4.

In the 11 individual benchmarks reported for both models, Qwen3.8-27B wins 7; this is a narrower head-to-head signal than the composite indexes.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Qwen3.8-27B

  • you value its reported benchmark strengths — it wins 7 of 11 exact shared results
  • you want the most recent training data — it shipped Aug 2026
  • you need open weights you can self-host or fine-tune

Choose Seed 2.1 Pro

  • you are already invested in the ByteDance ecosystem

At a glance

The differences that matter most.

Qwen3.8-27B
Alibaba Cloud / Qwen Team
Seed 2.1 Pro
ByteDance
Core performance indexes
LLM Stats Score
45.2
#30
46.4
#25
Reasoning
44.8
#31
47.2
#22
Coding
31.6
#39
33.7
#31
Agents
30.4
#31
31.3
#26
Cost, coverage & limits
Benchmark wins
7 of 11
4 of 11
Input price
— / M
— / M
Output price
— / M
— / M
Context window
262,144
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
Qwen3.8-27B
Seed 2.1 Pro
Math
31.0#68
39.1#20
Vision
33.1#18
34.2#12
Tool use
22.7#42
26.4#27
Multimodal
36.9#6
37.4#4
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

26 reported for Qwen3.8-27B · 94 for Seed 2.1 Pro

11 shared

Qwen3.8-27B outperforms in 7 benchmarks (Agents' Last Exam, BabyVision, CharXiv-R, ClawEval-MM, MathVision, SWE-Bench Pro, Terminal-Bench 2.1), while Seed 2.1 Pro is better at 4 benchmarks (ERQA, Humanity's Last Exam, NL2Repo, RealWorldQA).

Qwen3.8-27B shows notably better performance in the majority of benchmarks.

Sun Sep 06 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Qwen3.8-27B specifies input context (262,144 tokens). Only Qwen3.8-27B specifies output context (131,072 tokens).

Alibaba Cloud / Qwen Team
Qwen3.8-27B
Input262,144 tokens
Output131,072 tokens
ByteDance
Seed 2.1 Pro
Input- tokens
Output- tokens
Sun Sep 06 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Qwen3.8-27B and Seed 2.1 Pro support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Qwen3.8-27B

Text
Images
Audio
Video

Seed 2.1 Pro

Text
Images
Audio
Video

License

Usage and distribution terms

Qwen3.8-27B is licensed under Apache 2.0, while Seed 2.1 Pro uses a proprietary license.

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

Qwen3.8-27B

Apache 2.0

Open weights

Seed 2.1 Pro

Proprietary

Closed source

Release Timeline

When each model was launched

Qwen3.8-27B was released on 2026-08-14, while Seed 2.1 Pro was released on 2026-06-24.

Qwen3.8-27B is 2 months newer than Seed 2.1 Pro.

Qwen3.8-27B

Aug 14, 2026

3 weeks ago

1mo newer
Seed 2.1 Pro

Jun 24, 2026

2 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

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Qwen3.8-27B and Seed 2.1 Pro side-by-side, then vote on the output you prefer.

Qwen3.8-27B
✓ Preferred
Seed 2.1 Pro
Open in Playground

FAQ

Common questions about Qwen3.8-27B vs Seed 2.1 Pro.

Which is better, Qwen3.8-27B or Seed 2.1 Pro?

Qwen3.8-27B and Seed 2.1 Pro are closely matched on the LLM Stats Score at 45.2 and 46.4. Qwen3.8-27B is made by Alibaba Cloud / Qwen Team and Seed 2.1 Pro is made by ByteDance. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Qwen3.8-27B compare to Seed 2.1 Pro in benchmarks?

Qwen3.8-27B scores MathVision: 94.6%, OmniDocBench 1.5: 91.1%, LiveCodeBench v6: 90.3%, CharXiv-R: 90.2%, GPQA: 89.2%. Seed 2.1 Pro scores CharXiv-D: 95.5%, MathVision: 94.5%, MathVista: 90.7%, MathVerse: 89.7%, Video-MME: 89.2%.

What are the context window sizes for Qwen3.8-27B and Seed 2.1 Pro?

Qwen3.8-27B supports 262K tokens and Seed 2.1 Pro supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Qwen3.8-27B and Seed 2.1 Pro?

Key differences include LLM Stats Score (45.2 vs 46.4), licensing (Apache 2.0 vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes Qwen3.8-27B and Seed 2.1 Pro?

Qwen3.8-27B is developed by Alibaba Cloud / Qwen Team and Seed 2.1 Pro is developed by ByteDance.

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