Seedance 2.5

Seedance 2.5 is ByteDance's video model, announced on 31 July 2026 and rolled out through Dreamina and Doubao in China, with API access following on Volcano Ark and third-party gateways. Its headline is length: a single pass produces up to 30 seconds, so an ad with an opening, a demonstration and a closing beat fits in one generation instead of three stitched clips, and multi-round extension keeps the same subject running afterwards.

Control comes from reference material rather than prompt tricks. One request carries up to 50 assets - about 30 images, 10 video clips and 10 audio clips - used separately for character, product, scene, motion and rhythm, with timestamped direction and region-level editing, so a change to one area leaves the subject, background and the other beats intact. The endpoints we can check list 480p and 720p output in seven aspect ratios including 21:9 and 9:16, exporting MP4 or MOV, with speech, effects and score generated in the same pass at no surcharge. Leaving duration on automatic lets the model choose the clip length, which also changes the bill.

Pricing is per generated second and compounds quickly at 30 seconds: OpenRouter's model page showed about $0.103 a second at 480p in early September 2026, and resellers quote roughly $0.12 at 480p and $0.27 at 720p. ByteDance sells access through its own platform and through API providers rather than as a consumer credit plan, so there is no daily free allowance to lean on. One billing detail bites editors: upstream metering counts input seconds plus output seconds, so extending or restyling a clip as long as the finished piece costs about 20% more than generating that length from nothing. You are paying for reference-heavy long takes; if the job is a five-second shot, cheaper short-form models do it for less.