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Gemini 3.8 Flash vs Seed 2.1 Pro

Gemini 3.8 Flash leads the LLM Stats Score 51.8 to 46.7.

Google · ByteDance · Updated for 2026

Which is better?

Gemini 3.8 Flash leads the overall LLM Stats Score 51.8 to 46.7, ranking #11 overall.

In the 3 individual benchmarks reported for both models, Gemini 3.8 Flash 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 Gemini 3.8 Flash

  • overall performance matters — it scores 51.8 and ranks #11 on LLM Stats
  • your work emphasizes coding and agents — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 2 of 3 exact shared results
  • you want the most recent training data — it shipped Sep 2026

Choose Seed 2.1 Pro

  • you are already invested in the ByteDance ecosystem

At a glance

The differences that matter most.

Gemini 3.8 Flash
Google
Seed 2.1 Pro
ByteDance
Core performance indexes
LLM Stats Score
51.8
#11
46.7
#23
Reasoning
47.6
#21
47.6
#22
Coding
41.3
#10
34.4
#29
Agents
36.9
#13
31.9
#24
Cost, coverage & limits
Benchmark wins
2 of 3
1 of 3
Input price
$0.75 / M
— / M
Output price
$3.75 / M
— / M
Context window
1,048,576
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

3 shared
Index
Gemini 3.8 Flash
Seed 2.1 Pro
Vision
34.4#11
34.2#12
Tool use
28.4#20
27.8#22
Multimodal
35.3#10
37.5#4
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

13 reported for Gemini 3.8 Flash · 94 for Seed 2.1 Pro

3 shared

Gemini 3.8 Flash outperforms in 2 benchmarks (LVBench, Terminal-Bench 2.1), while Seed 2.1 Pro is better at 1 benchmark (CharXiv-R).

Gemini 3.8 Flash shows notably better performance in the majority of benchmarks.

Wed Sep 02 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Gemini 3.8 Flash specifies input context (1,048,576 tokens). Only Gemini 3.8 Flash specifies output context (65,536 tokens).

Google
Gemini 3.8 Flash
Input1,048,576 tokens
Output65,536 tokens
ByteDance
Seed 2.1 Pro
Input- tokens
Output- tokens
Wed Sep 02 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Gemini 3.8 Flash and Seed 2.1 Pro support multimodal inputs.

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

Gemini 3.8 Flash

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.

Gemini 3.8 Flash

Proprietary

Closed source

Seed 2.1 Pro

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.8 Flash was released on 2026-09-02, while Seed 2.1 Pro was released on 2026-06-24.

Gemini 3.8 Flash is 2 months newer than Seed 2.1 Pro.

Gemini 3.8 Flash

Sep 2, 2026

0 days ago

2mo newer
Seed 2.1 Pro

Jun 24, 2026

2 months ago

Knowledge Cutoff

When training data ends

Gemini 3.8 Flash has a documented knowledge cutoff of 2026-03-31, while Seed 2.1 Pro's cutoff date is not specified.

We can confirm Gemini 3.8 Flash's training data extends to 2026-03-31, but cannot make a direct comparison without Seed 2.1 Pro's cutoff date.

Gemini 3.8 Flash

Mar 2026

Seed 2.1 Pro

—

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Gemini 3.8 Flash and Seed 2.1 Pro side-by-side, then vote on the output you prefer.

Gemini 3.8 Flash
✓ Preferred
Seed 2.1 Pro
Open in Playground

FAQ

Common questions about Gemini 3.8 Flash vs Seed 2.1 Pro.

Which is better, Gemini 3.8 Flash or Seed 2.1 Pro?

Gemini 3.8 Flash leads the LLM Stats Score 51.8 to 46.7. Gemini 3.8 Flash is made by Google 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 Gemini 3.8 Flash compare to Seed 2.1 Pro in benchmarks?

Gemini 3.8 Flash scores Terminal-Bench 2.1: 89.4%, LVBench: 87.1%, CharXiv-R: 86.2%, LABBench2: 86.2%, DeepSWE 1.1: 73.7%. 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 Gemini 3.8 Flash and Seed 2.1 Pro?

Gemini 3.8 Flash 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 Gemini 3.8 Flash and Seed 2.1 Pro?

Key differences include LLM Stats Score (51.8 vs 46.7). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3.8 Flash and Seed 2.1 Pro?

Gemini 3.8 Flash is developed by Google and Seed 2.1 Pro is developed by ByteDance.

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