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Hy3 vs Seed 2.1 Pro

Hy3 and Seed 2.1 Pro are closely matched at 42.9 and 47.0 on the LLM Stats Score.

Tencent · ByteDance · Updated for 2026

Which is better?

Hy3 and Seed 2.1 Pro are closely matched on the overall LLM Stats Score at 42.9 and 47.0.

In the 14 individual benchmarks reported for both models, Seed 2.1 Pro wins 10; 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 Hy3

  • you want the most recent training data — it shipped Jul 2026
  • you need open weights you can self-host or fine-tune

Choose Seed 2.1 Pro

  • your work emphasizes reasoning — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 10 of 14 exact shared results

At a glance

The differences that matter most.

Hy3
Tencent
Seed 2.1 Pro
ByteDance
Core performance indexes
LLM Stats Score
42.9
#39
47.0
#20
Reasoning
42.9
#37
47.9
#18
Coding
35.0
#27
36.0
#25
Agents
28.2
#36
33.1
#22
Cost, coverage & limits
Benchmark wins
4 of 14
10 of 14
Input price
— / M
— / M
Output price
— / M
— / M
Context window
—
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Hy3
Seed 2.1 Pro
Math
34.6#43
39.8#15
Tool use
23.2#39
27.9#17
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

31 reported for Hy3 · 94 for Seed 2.1 Pro

14 shared

Hy3 outperforms in 4 benchmarks (HorizonMath, MathArena Apex, SWE-Bench Pro, Terminal-Bench 2.1), while Seed 2.1 Pro is better at 10 benchmarks (APEX-Agents, BrowseComp, DeepSWE, FrontierScience Olympiad, FrontierScience Research, MCP Atlas, NL2Repo, SuperChem, Toolathlon, WildClawBench).

Seed 2.1 Pro shows notably better performance in the majority of benchmarks.

Fri Aug 28 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Input capabilities

Documented input modalities across available providers

Seed 2.1 Pro supports multimodal inputs, whereas Hy3 does not.

Seed 2.1 Pro can handle both text and other forms of data like images, making it suitable for multimodal applications.

Hy3

Text
Images
Audio
Video

Seed 2.1 Pro

Text
Images
Audio
Video

License

Usage and distribution terms

Hy3 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.

Hy3

Apache 2.0

Open weights

Seed 2.1 Pro

Proprietary

Closed source

Release Timeline

When each model was launched

Hy3 was released on 2026-07-06, while Seed 2.1 Pro was released on 2026-06-24.

Hy3 is 0 month newer than Seed 2.1 Pro.

Hy3

Jul 6, 2026

1 months ago

1w 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 Hy3 and Seed 2.1 Pro side-by-side, then vote on the output you prefer.

Hy3
✓ Preferred
Seed 2.1 Pro
Open in Playground

FAQ

Common questions about Hy3 vs Seed 2.1 Pro.

Which is better, Hy3 or Seed 2.1 Pro?

Hy3 and Seed 2.1 Pro are closely matched on the LLM Stats Score at 42.9 and 47.0. Hy3 is made by Tencent 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 Hy3 compare to Seed 2.1 Pro in benchmarks?

Hy3 scores DeepSearchQA: 91.0%, GPQA: 90.4%, IMO-AnswerBench: 90.0%, BrowseComp: 84.2%, MCP Atlas: 79.1%. 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 main differences between Hy3 and Seed 2.1 Pro?

Key differences include LLM Stats Score (42.9 vs 47.0), multimodal support (no vs yes), licensing (Apache 2.0 vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes Hy3 and Seed 2.1 Pro?

Hy3 is developed by Tencent and Seed 2.1 Pro is developed by ByteDance.

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