Model Comparison

Claude Opus 4.6 vs Seed 2.1 ProWhich is better in 2026?

Seed 2.1 Pro significantly outperforms across most benchmarks.

Verdict: Claude Opus 4.6 vs Seed 2.1 Pro — which is better?

Claude Opus 4.6 (by Anthropic) 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.

Claude Opus 4.6 outperforms in 1 benchmarks (CyberGym), while Seed 2.1 Pro is better at 6 benchmarks (BrowseComp, CharXiv-R, Humanity's Last Exam, MCP Atlas, MMMU-Pro, OSWorld). Seed 2.1 Pro significantly outperforms across most benchmarks.

Choose Claude Opus 4.6 if…

  • you want predictable pricing at $5.00/M input and $25.00/M output

Choose Seed 2.1 Pro if…

  • you want the strongest raw capability — it leads on 6 of 7 shared benchmarks
  • you want the most recent training data — it shipped Jun 2026
Want to compare interactively?Try the playground

Performance Benchmarks

Comparative analysis across standard metrics

7 benchmarks

Claude Opus 4.6 outperforms in 1 benchmarks (CyberGym), while Seed 2.1 Pro is better at 6 benchmarks (BrowseComp, CharXiv-R, Humanity's Last Exam, MCP Atlas, MMMU-Pro, OSWorld).

Seed 2.1 Pro significantly outperforms across most benchmarks.

Thu Jun 25 2026 • llm-stats.com

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only Claude Opus 4.6 specifies input context (1,000,000 tokens). Only Claude Opus 4.6 specifies output context (128,000 tokens).

Anthropic
Claude Opus 4.6
Input1,000,000 tokens
Output128,000 tokens
ByteDance
Seed 2.1 Pro
Input- tokens
Output- tokens
Thu Jun 25 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Opus 4.6 and Seed 2.1 Pro support multimodal inputs.

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

Claude Opus 4.6

Text
Images
Audio
Video

Seed 2.1 Pro

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Opus 4.6

Proprietary

Closed source

Seed 2.1 Pro

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 4.6 was released on 2026-02-05, while Seed 2.1 Pro was released on 2026-06-24.

Seed 2.1 Pro is 5 months newer than Claude Opus 4.6.

Claude Opus 4.6

Feb 5, 2026

4 months ago

Seed 2.1 Pro

Jun 24, 2026

1 days ago

4mo 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

Anthropic
Larger context window (1,000,000 tokens)
Higher CyberGym score (73.8% vs 70.2%)
ByteDance
Higher BrowseComp score (86.2% vs 84.0%)
Higher CharXiv-R score (86.4% vs 77.4%)
Higher Humanity's Last Exam score (55.7% vs 53.1%)
Higher MCP Atlas score (83.8% vs 62.7%)
Higher MMMU-Pro score (82.7% vs 77.3%)
Higher OSWorld score (78.8% vs 72.7%)

Detailed Comparison

AI Model Comparison Table
Feature
Anthropic
Claude Opus 4.6
ByteDance
Seed 2.1 Pro

FAQ

Common questions about Claude Opus 4.6 vs Seed 2.1 Pro.

Which is better, Claude Opus 4.6 or Seed 2.1 Pro?

Seed 2.1 Pro significantly outperforms across most benchmarks. Claude Opus 4.6 is made by Anthropic 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 Claude Opus 4.6 compare to Seed 2.1 Pro in benchmarks?

Claude Opus 4.6 scores Vending-Bench 2: 100.0%, AIME 2025: 99.8%, Tau2 Telecom: 99.3%, Graphwalks parents >128k: 95.4%, Tau2 Retail: 91.9%. 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 Claude Opus 4.6 and Seed 2.1 Pro?

Claude Opus 4.6 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.

Who makes Claude Opus 4.6 and Seed 2.1 Pro?

Claude Opus 4.6 is developed by Anthropic and Seed 2.1 Pro is developed by ByteDance.

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