Doubao Seed 2.1 Pro
Doubao Seed 2.1
ByteDance's current flagship, now with a million-token window and strong video understanding.
Updated
The read
Seed 2.1 Pro succeeded Seed 2.0 Pro in June and gained a million-token version in a September update. It is a closed multimodal model with strong image and video understanding, and ByteDance prices it at a small fraction of American flagships. Neither major independent leaderboard has rated it, and its published terminal scores trail the leading Chinese open models, so its score here is cautious. Outside China, the usual questions about hosting and data policy apply.
Where it shines
- Strong image and video understanding
- Million-token context since the September update
- Priced far below American flagships
Worth knowing first
- Not yet rated by the independent leaderboards
- Closed weights and Chinese-hosted, which rules it out for some teams
Index score
82.6
Provisional. This score is read from the product's public capability, not from the one-prompt rebuild the fully reviewed entries went through, so treat it as a placing rather than a verdict.
- Rank
- 32 of 73
- Builds
- LLMs
- Category
- Frontier
- Output
- Text, images and video in, text out
- Pricing
- Paid only
- Best for
- Multimodal work inside the Chinese ecosystem at low cost
Scores are our own editorial judgement, weighted craft 55, speed 10, control 15 and value 20.
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