One 30-second Seedance 2.5 clip or three 10-second clips: price

A single 30-second Seedance 2.5 clip costs exactly as much as three 10-second clips on Sume, because the price is video tokens and tokens are linear in seconds. At 720p 16:9 both come to 648,000 tokens, $13.8672 at fal list and about $17.33 on Sume after the x 1.25 house margin. So choose by creative need, not by price.

The arithmetic

Tokens = (width x height x seconds x 24) / 1024, charged at fal's $0.0214 per 1,000 tokens for 480p and 720p. Doubling seconds doubles tokens; there is no per-job fee in the rate card.

Sume's video docs say it bills provider list x 1.25 on every video model.

Where the real cost difference is

The reserve is equal, the retake economics are not. If one beat in a 30-second take is wrong, you pay for 30 seconds again; with three 10-second shots you pay about $5.78 at 720p to redo one. Against that, a single take keeps continuity with no cuts. Sume accepts up to 30 seconds on Seedance 2.5 and 15 seconds on the other Seedance models, per the Video Router docs.

Both choices also cost the same as the longest slice when you chain: see the 720p price table for each length.