Seedance 2.5 AI動画生成

Seedance 2.5 is ByteDance's newest flagship video model and the longest-take generator on FlyAIgh: one continuous shot can run from 4 to 30 seconds, against a 15-second ceiling on the Seedance 2.0 family and 8 to 12 seconds on most competing flagships. That matters because a 30-second take is a shot that never needs stitching — no hidden cut, no continuity break, no frame-matching between clips.

It also carries the largest reference budget on the platform. A single generation accepts up to 30 reference images, where the 2.0 variants cap at nine. A full cast, a set of props and a location can therefore anchor the same shot at once, which is the practical difference between animating one subject and staging a scene. Reference images carry no surcharge on this model — price is driven by output seconds and resolution alone.

Four input modes are available from one account: text-to-video, image-to-video from a single first frame, first-and-last-frame interpolation, and multimodal reference-to-video. Native synchronized audio — dialogue, ambience and music — is produced together with the video in every mode, with no separate pass. Seven aspect ratios are supported: 16:9, 9:16, 4:3, 1:1, 3:4, 21:9, plus an adaptive option that lets the model choose the best framing for the prompt.

FlyAIgh prices Seedance 2.5 at 15.3 credits per output second at 720p — 77 credits for a 5-second clip, 153 for 10 seconds, and 459 for a full 30-second take. Five resolution tiers are offered: 480p at 0.45x the 720p rate, 720p itself, then upscaled 1080p, 2K and 4K at 1.16x, 1.21x and 1.31x. Unlike Seedance 2.0 Pro, 2.5 has no native-resolution render above 720p — everything above it is upscaled — so choose 2.0 Pro when true native 1080p or native 4K capture is the requirement.

One billing detail is worth knowing before you start: when you supply a reference video, the model bills the input video's duration as well as the output's. Feeding a 10-second reference to produce a 4-second clip is charged as 14 seconds. FlyAIgh shows the exact credit total before you generate, so the number is never a surprise.

Choose Seedance 2.5 for long unbroken shots, for scenes that need several fixed subjects held consistent, or for any sequence where a stitch would show. Choose Seedance 2.0 Pro when the shot is short and native 4K or the lowest cost per second matters more than length.