Seedance Video Upload Failed? Seedance Reference Video Specs Explained
Seedance reference videos must be 2–15 seconds, under 50MB, 24–60 FPS and within a strict total pixel range. See why 4K and small 360p clips both fail.
Why does Seedance reject my reference video?
Seedance can take up to three reference videos alongside images and audio, and use them to guide motion, camera movement and style in a new clip. That flexibility comes with input rules that are different from most other platforms, so a clip that another tool accepted can still be refused here.
The two limits that catch people most often are the 50MB size cap per clip and a rule on the total number of pixels in each frame. Both are easy to miss because a normal-looking video from a phone or camera can break them without anything looking wrong.
Seedance reference video limits
Up to 3 videos, each 2 to 15 seconds and 15 seconds combined, MP4 or MOV, up to 50MB per clip, 24 to 60 FPS, each side 300–6000px, total frame pixels between 409,600 and 2,086,876, aspect ratio between 0.4 and 2.5.
The total pixel rule: why both 4K and 360p fail
Seedance does not just check width and height separately. It multiplies them, and the result has to land between 409,600 and 2,086,876 pixels. A 1920×1080 frame is 2,073,600 pixels, just inside the limit. A UHD 4K frame (3840×2160) is over 8 million, so it fails. At the other end, a 640×360 clip is only 230,400 pixels and fails for being too small, while 854×480 just passes. If your footage is 4K, scale it to 1080p. If it is a small download, export it at 720p or higher rather than uploading the original.
50MB per clip is the tightest limit
Most AI video platforms allow 100–200MB. Seedance allows 50MB per reference clip. A 15-second 1080p clip from a phone recording at a high bitrate, or almost any 4K or ProRes original, will go over. Re-encoding to H.264 at 1080p with a sensible bitrate usually brings a 15-second clip well under 50MB without visible quality loss.
Three clips share one 15-second budget
You can give Seedance up to three reference videos, but their combined length cannot exceed 15 seconds. Three 6-second clips (18 seconds) will be rejected even though each one is fine on its own. Decide which moment of each shot actually matters for motion or camera reference, trim to that, and keep the total at 15 seconds or less. For example: 5 + 5 + 5, or 8 + 4 + 3.
Very wide or very tall framing
The aspect ratio of each reference must be between 0.4 and 2.5 (width divided by height). Standard 16:9 (1.78), 9:16 vertical (0.56) and 2.39:1 cinemascope (2.39) all pass. Extreme panoramic crops wider than 2.5:1 or very tall strips narrower than 0.4 will not. Crop or letterbox those to a standard ratio first.
Common reasons Seedance rejects a reference video
AI video encoders require strict video specifications in browser and cloud AI server environments. Upload errors typically occur due to the reasons below.
Preparing a reference video for Seedance
Select Seedance in FixMyVideoForAI and drop in your clip. The tool checks duration, file size, resolution, frame rate and codec against Seedance's limits and shows exactly which items fail.
Converting re-encodes the clip to MP4 (H.264) at a constant frame rate, scales oversized footage down to 1080p and trims the length to a whole number of seconds so you can plan your 15-second budget across multiple references. Everything runs inside your browser, so your footage never leaves your computer.
Convert to Compliant Video Now (Seedance)
Safely convert in your browser to MP4 + H.264 + CFR without software installation.
Frequently Asked Questions
Seedance limits the total number of pixels per frame to about 2.09 million. 1080p is about 2.07 million and passes. 4K is over 8 million and fails, regardless of file size.