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Seed 2.1 Pro vs Solar Pro 4

Seed 2.1 Pro leads the LLM Stats Score 47.0 to 36.0.

ByteDance · Upstage · Updated for 2026

Which is better?

Seed 2.1 Pro leads the overall LLM Stats Score 47.0 to 36.0, ranking #20 overall.

In the 2 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 Seed 2.1 Pro

  • overall performance matters — it scores 47.0 and ranks #20 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 2 of 2 exact shared results

Choose Solar Pro 4

  • you want the most recent training data — it shipped Aug 2026

At a glance

The differences that matter most.

Seed 2.1 Pro
ByteDance
Solar Pro 4
Upstage
Core performance indexes
LLM Stats Score
47.0
#20
36.0
#72
Reasoning
47.9
#18
35.6
#71
Coding
36.0
#25
22.1
#73
Agents
33.1
#22
13.8
#84
Cost, coverage & limits
Benchmark wins
2 of 2
0 of 2
Input price
— / M
$0.30 / M
Output price
— / M
$1.20 / M
Context window
—
524,288

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Seed 2.1 Pro
Solar Pro 4
Math
39.8#15
32.0#55
Tool use
27.9#17
15.3#81
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

94 reported for Seed 2.1 Pro · 9 for Solar Pro 4

2 shared

Seed 2.1 Pro outperforms in 2 benchmarks (BrowseComp, Terminal-Bench 2.1), while Solar Pro 4 is better at 0 benchmarks.

Seed 2.1 Pro significantly outperforms across most 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 Solar Pro 4 specifies input context (524,288 tokens). Only Solar Pro 4 specifies output context (131,072 tokens).

ByteDance
Seed 2.1 Pro
Input- tokens
Output- tokens
Upstage
Solar Pro 4
Input524,288 tokens
Output131,072 tokens
Fri Aug 28 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Seed 2.1 Pro supports multimodal inputs, whereas Solar Pro 4 does not.

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

Seed 2.1 Pro

Text
Images
Audio
Video

Solar Pro 4

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.

Seed 2.1 Pro

Proprietary

Closed source

Solar Pro 4

Proprietary

Closed source

Release Timeline

When each model was launched

Seed 2.1 Pro was released on 2026-06-24, while Solar Pro 4 was released on 2026-08-06.

Solar Pro 4 is 1 month newer than Seed 2.1 Pro.

Seed 2.1 Pro

Jun 24, 2026

2 months ago

Solar Pro 4

Aug 6, 2026

3 weeks ago

1mo 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→

Judge for yourself.

Run your own prompts against Seed 2.1 Pro and Solar Pro 4 side-by-side, then vote on the output you prefer.

Seed 2.1 Pro
✓ Preferred
Solar Pro 4
Open in Playground

FAQ

Common questions about Seed 2.1 Pro vs Solar Pro 4.

Which is better, Seed 2.1 Pro or Solar Pro 4?

Seed 2.1 Pro leads the LLM Stats Score 47.0 to 36.0. Seed 2.1 Pro is made by ByteDance and Solar Pro 4 is made by Upstage. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Seed 2.1 Pro compare to Solar Pro 4 in benchmarks?

Seed 2.1 Pro scores CharXiv-D: 95.5%, MathVision: 94.5%, MathVista: 90.7%, MathVerse: 89.7%, Video-MME: 89.2%. Solar Pro 4 scores AIME 2026: 95.3%, GPQA: 89.0%, LiveCodeBench: 87.8%, MMLU-Pro: 86.3%, AA-LCR: 71.0%.

What are the context window sizes for Seed 2.1 Pro and Solar Pro 4?

Seed 2.1 Pro supports an unknown number of tokens and Solar Pro 4 supports 524K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Seed 2.1 Pro and Solar Pro 4?

Key differences include LLM Stats Score (47.0 vs 36.0), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Seed 2.1 Pro and Solar Pro 4?

Seed 2.1 Pro is developed by ByteDance and Solar Pro 4 is developed by Upstage.

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