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Laguna S 2.1 vs Seed 2.1 Pro

Laguna S 2.1 and Seed 2.1 Pro are closely matched at 41.4 and 47.0 on the LLM Stats Score.

Poolside · ByteDance · Updated for 2026

Which is better?

Laguna S 2.1 and Seed 2.1 Pro are closely matched on the overall LLM Stats Score at 41.4 and 47.0.

In the 3 individual benchmarks reported for both models, Seed 2.1 Pro wins 2; 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 Laguna S 2.1

  • 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

  • you value its reported benchmark strengths — it wins 2 of 3 exact shared results

At a glance

The differences that matter most.

Laguna S 2.1
Poolside
Seed 2.1 Pro
ByteDance
Core performance indexes
LLM Stats Score
41.4
#43
47.0
#20
Reasoning
41.5
#40
47.9
#18
Coding
33.1
#37
36.0
#25
Agents
25.7
#43
33.1
#22
Cost, coverage & limits
Benchmark wins
1 of 3
2 of 3
Input price
$0.10 / M
— / M
Output price
$0.20 / M
— / M
Context window
1,048,576
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Laguna S 2.1
Seed 2.1 Pro
Tool use
18.9#56
27.9#17
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

6 reported for Laguna S 2.1 · 94 for Seed 2.1 Pro

3 shared

Laguna S 2.1 outperforms in 1 benchmarks (SWE-Bench Pro), while Seed 2.1 Pro is better at 2 benchmarks (Terminal-Bench 2.1, Toolathlon).

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

Context Window

Maximum input and output token capacity

Only Laguna S 2.1 specifies input context (1,048,576 tokens).

Poolside
Laguna S 2.1
Input1,048,576 tokens
Output- tokens
ByteDance
Seed 2.1 Pro
Input- tokens
Output- tokens
Fri Aug 28 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Seed 2.1 Pro supports multimodal inputs, whereas Laguna S 2.1 does not.

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

Laguna S 2.1

Text
Images
Audio
Video

Seed 2.1 Pro

Text
Images
Audio
Video

License

Usage and distribution terms

Laguna S 2.1 is licensed under OpenMDW License v1.1, 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.

Laguna S 2.1

OpenMDW License v1.1

Open weights

Seed 2.1 Pro

Proprietary

Closed source

Release Timeline

When each model was launched

Laguna S 2.1 was released on 2026-07-21, while Seed 2.1 Pro was released on 2026-06-24.

Laguna S 2.1 is 1 month newer than Seed 2.1 Pro.

Laguna S 2.1

Jul 21, 2026

1 months ago

3w 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 Laguna S 2.1 and Seed 2.1 Pro side-by-side, then vote on the output you prefer.

Laguna S 2.1
✓ Preferred
Seed 2.1 Pro
Open in Playground

FAQ

Common questions about Laguna S 2.1 vs Seed 2.1 Pro.

Which is better, Laguna S 2.1 or Seed 2.1 Pro?

Laguna S 2.1 and Seed 2.1 Pro are closely matched on the LLM Stats Score at 41.4 and 47.0. Laguna S 2.1 is made by Poolside 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 Laguna S 2.1 compare to Seed 2.1 Pro in benchmarks?

Laguna S 2.1 scores SWE-bench Multilingual: 78.5%, Terminal-Bench 2.1: 70.2%, SWE-Bench Pro: 59.4%, Toolathlon: 49.7%, SWE Atlas - Codebase QnA: 46.2%. 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 Laguna S 2.1 and Seed 2.1 Pro?

Laguna S 2.1 supports 1.0M 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 Laguna S 2.1 and Seed 2.1 Pro?

Key differences include LLM Stats Score (41.4 vs 47.0), multimodal support (no vs yes), licensing (OpenMDW License v1.1 vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes Laguna S 2.1 and Seed 2.1 Pro?

Laguna S 2.1 is developed by Poolside and Seed 2.1 Pro is developed by ByteDance.

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