The model infrastructure ByteDance operates in AI
ByteDance builds Seedance, the model unit holding the top rank in our video ranking table. The most unusual thing about this vendor is not the model but its documentation: its own specification page for Seedance 2.5 registers no resolution figure at all, and extracting the real ceiling requires going to another distributor pricing list.
- Seedance holds the top video rank
- deployment date embedded in the model id
- resolution specification from a third party
Last checked: This is a reference page. It is re-checked against the vendor sources and updated when a new version ships. Change log
Model families
The model lines: Seedance for video, Seedream for images.
Versions
| Versions | Deployed | Status | Model families |
|---|---|---|---|
| Seedance 2.5 | current | Seedance | |
| Seedream 5.0 Pro | current | Seedream |
A documentation pattern few other vendors follow
ByteDance embeds the deployment date inside the model id. From its own API documentation the ids are doubao-seedance-1-0-lite-i2v-250428, doubao-seedance-1-0-pro-250528, doubao-seedance-1-5-pro-251215, doubao-seedance-2-0-260128 and doubao-seedance-2-5-260628. The last six digits are year, month and day. So the deployment timeline of this production line can be extracted from the id list alone, with no changelog required. None of the other vendors in this reference carry this structure.
Documentation that has fallen behind actual model deployment
The page at seed.bytedance.com/en/seedance still registers the Seedance 1.0 specification and headlines "1080p videos". A separate Seedance 2.5 page exists on the same domain and is complete, but across its entire text a resolution figure is never registered; it documents thirty seconds of storytelling, reference control and green-screen editing, and says nothing about output capacity in pixels.
The Volcano Engine API documentation also renders in JavaScript, and the raw page text registers no resolution figure either. We verified this ourselves, since we initially assumed the numbers would be documented there.
The practical result: the only place this production line resolution ceiling is registered in readable text is the Runway pricing list. There, Seedance 2.0 has four rows going up to 4K, and Seedance 2.5 has only two, 480p and 720p. So the evidence for the claim that the newer version has a lower ceiling is not extracted from its own vendor; it comes from a distributor that resells it.
What this documentation does not claim
ByteDance also owns TikTok, and we register nothing about that here, because it has no bearing on the model architecture. We have also not extracted the official Seedance rate in yuan on the Volcano Engine console and we do not fabricate a figure; the rate you see in this reference is the Runway rate and it is explicitly registered under Runway name.
Documented strengths
- Seedance 2.5 holds the top rank in our video ranking table
- the deployment date is registered inside the model id, so the timeline is extractable with no changelog
- it has model units deployed in two categories: video with Seedance and images with Seedream
- the same production line is distributed across several platforms, so you are not tied to a single gateway
Known weaknesses and limits
- The Seedance 2.5 specification page registers no resolution figure at all, and the Seedance 1.0 page has not been updated.
- The API documentation renders in JavaScript, so its numbers are not straightforwardly extractable.
- The resolution ceiling of this production line can only be extracted from another distributor pricing list.
- It publishes no country list and its official deployment route is a Chinese console, so the Iran column is logged as unknown.
Technical verdict
If you want the highest video quality, ByteDance model unit is currently the top pick in our table. Just do not expect to extract its full specification from ByteDance own documentation; for the numbers you have to go to whoever distributes it.
Frequently raised questions, with documented answers
Who owns Seedance and where can it be deployed?
It belongs to ByteDance. It is deployed on their own cloud infrastructure, Volcano Engine, and is simultaneously distributed through the Runway API and Higgsfield. So it is one model unit reaching you through several routes.
Why is the Seedance 2.5 resolution not registered on its own page?
We do not know why, only that it is not registered. We checked the entire text of that page and a resolution figure never appears. That is why in this reference the figure is attributed to Runway rather than to ByteDance.