Seedance 2.5 reference video limits: 200 MB, 24-60 fps

BytePlus's Seedance 2.5 tutorial says a single reference video must not exceed 200 MB and must run at 24 to 60 frames per second. Reference audio is limited to 2 to 30 seconds per clip. Check those numbers on your files before sending anything; Sume's pages that I read do not publish matching per-file limits.

Vendor numbers are from the BytePlus page, read 2026-10-01. Sume details are from Video generation and Video Router.

What are the BytePlus reference-file limits?

The tutorial gives separate limits for video and audio references. The audio list also names the accepted input methods and formats.

What does Sume's Seedance row say?

Sume lists seedance-2.5 at 4 to 30 seconds with 480p, 720p and 1080p output. The docs also say audio and video references are honored by the Seedance 2.x models, and that only models whose supported_input_references lists a type accept that type. I found no Sume page stating a reference file size or frame-rate limit, so treat the BytePlus numbers as a safe envelope rather than a Sume guarantee.

How do I check a clip before I send it?

Read the model entry from the catalog first: supported_input_references tells you whether video_url and audio_url are accepted at all. Then check your file against the vendor limits above. If a clip is over 200 MB or outside 24 to 60 fps, re-encode it before upload.

For what a reference can steer, see Seedance 2.5 reference limits.

What if a reference is rejected?

Treat the rejection as a request-shape problem, not a transient failure. Fix the file or drop the reference, then submit a new job. Sume's docs say a parameter a model does not list is rejected rather than dropped, so a clean error is the expected outcome for an unsupported input.