Model Comparison

Kimi K2.6 vs Seed 2.1 ProWhich is better in 2026?

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

Verdict: Kimi K2.6 vs Seed 2.1 Pro — which is better?

Kimi K2.6 (by Moonshot AI) and Seed 2.1 Pro (by ByteDance) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Kimi K2.6 outperforms in 3 benchmarks (BrowseComp, CharXiv-R, SWE-Bench Pro), while Seed 2.1 Pro is better at 7 benchmarks (APEX-Agents, BabyVision, Humanity's Last Exam, MathVision, MMMU-Pro, SciCode, Toolathlon). Seed 2.1 Pro shows notably better performance in the majority of benchmarks.

Choose Kimi K2.6 if…

  • you need open weights you can self-host or fine-tune

Choose Seed 2.1 Pro if…

  • you want the strongest raw capability — it leads on 7 of 10 shared benchmarks
  • you want the most recent training data — it shipped Jun 2026

Performance Benchmarks

Comparative analysis across standard metrics

10 benchmarks

Kimi K2.6 outperforms in 3 benchmarks (BrowseComp, CharXiv-R, SWE-Bench Pro), while Seed 2.1 Pro is better at 7 benchmarks (APEX-Agents, BabyVision, Humanity's Last Exam, MathVision, MMMU-Pro, SciCode, Toolathlon).

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

Sun Jul 26 2026 • llm-stats.com

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only Kimi K2.6 specifies input context (262,144 tokens). Only Kimi K2.6 specifies output context (131,072 tokens).

Moonshot AI
Kimi K2.6
Input262,144 tokens
Output131,072 tokens
ByteDance
Seed 2.1 Pro
Input- tokens
Output- tokens
Sun Jul 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Kimi K2.6 and Seed 2.1 Pro support multimodal inputs.

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

Kimi K2.6

Text
Images
Audio
Video

Seed 2.1 Pro

Text
Images
Audio
Video

License

Usage and distribution terms

Kimi K2.6 is licensed under Modified MIT License, 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.

Kimi K2.6

Modified MIT License

Open weights

Seed 2.1 Pro

Proprietary

Closed source

Release Timeline

When each model was launched

Kimi K2.6 was released on 2026-04-20, while Seed 2.1 Pro was released on 2026-06-24.

Seed 2.1 Pro is 2 months newer than Kimi K2.6.

Kimi K2.6

Apr 20, 2026

3 months ago

Seed 2.1 Pro

Jun 24, 2026

1 months ago

2mo newer

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→

Key Takeaways

Moonshot AI
Larger context window (262,144 tokens)
Has open weights
Higher BrowseComp score (86.3% vs 86.2%)
Higher CharXiv-R score (86.7% vs 86.4%)
Higher SWE-Bench Pro score (58.6% vs 57.5%)
ByteDance
Higher APEX-Agents score (33.8% vs 27.9%)
Higher BabyVision score (73.7% vs 68.5%)
Higher Humanity's Last Exam score (55.7% vs 36.4%)
Higher MathVision score (94.5% vs 93.2%)
Higher MMMU-Pro score (82.7% vs 80.1%)
Higher SciCode score (59.8% vs 52.2%)
Higher Toolathlon score (50.6% vs 50.0%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Kimi K2.6 and Seed 2.1 Pro side-by-side, then vote on the output you prefer.

Kimi K2.6
✓ Preferred
Seed 2.1 Pro
Open in Playground
AI Model Comparison Table
Feature
Moonshot AI
Kimi K2.6
ByteDance
Seed 2.1 Pro

FAQ

Common questions about Kimi K2.6 vs Seed 2.1 Pro.

Which is better, Kimi K2.6 or Seed 2.1 Pro?

Seed 2.1 Pro shows notably better performance in the majority of benchmarks. Kimi K2.6 is made by Moonshot AI and Seed 2.1 Pro is made by ByteDance. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Kimi K2.6 compare to Seed 2.1 Pro in benchmarks?

Kimi K2.6 scores V*: 96.9%, AIME 2026: 96.4%, MathVision: 93.2%, HMMT Feb 26: 92.7%, GPQA: 90.5%. 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 Kimi K2.6 and Seed 2.1 Pro?

Kimi K2.6 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 Kimi K2.6 and Seed 2.1 Pro?

Key differences include licensing (Modified MIT License vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes Kimi K2.6 and Seed 2.1 Pro?

Kimi K2.6 is developed by Moonshot AI and Seed 2.1 Pro is developed by ByteDance.

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