Seedance 2.5 or 2.0? Four questions that pick the model on Sume

Choose Seedance 2.5 when you need a clip longer than 15 seconds; otherwise ask whether the 2.0 family is enough. At 720p, a 10-second clip is $5.78 on 2.5 and $3.78 on Seedance 2.0 on Sume.

The four questions below take about a minute and cover the differences that show up in the Sume catalog.

Question 1: does the clip run past 15 seconds?

Seedance 2.0, 2.0 Fast and 2.0 Mini accept 4-15 seconds in the Video Router catalog. Seedance 2.5 accepts 4-30. If you need 16 to 30 seconds in one take, 2.5 is the only Seedance row that can do it. Check the catalog before you assume another family matches it.

Question 2: is the price gap worth it?

Sume's provider list rate for 2.5 is higher per video token than for 2.0, and the gap carries through to every clip.

Question 3: do you need 1080p?

Both Seedance 2.0 and 2.5 list 480p, 720p and 1080p. Fast and Mini stop at 720p. So 1080p alone does not force 2.5. It forces 2.0 or 2.5, and the price table above shows the difference at 15 seconds.

Do not assume 4K. The Seedance rows list 480p, 720p and 1080p only, so plan for 1080p as the top.

Question 4: is this a draft or a keeper?

If you are screening prompts, use Mini or Fast at 480p. A 5-second Mini draft at 480p is $0.44 and a Fast draft is $0.71. The keeper can then be 2.0 or 2.5 depending on the first three questions.

No tier takes a seed on Sume, so a draft cannot be promoted. The keeper is a new take.

A worked example

Take a 12-second product loop for a landing page, 16:9, 720p. Question 1: 12 seconds is under 15, so 2.0 is allowed. Question 2: the clip is $4.54 on 2.0 and $6.94 on 2.5, so the newer model costs $2.40 more per take. Question 3: 720p is fine, no need for 1080p. Question 4: this is the keeper, but you will likely run four or five takes to get one you like.

Five takes on 2.0 is $22.70; five on 2.5 is $34.70. The gap is what you pay for the newer model across the whole search, and it is usually the number to decide on, not the price of one clip. Run the first two takes at 480p to cut that bill before you commit to 720p.

Putting the answers together

• Over 15 seconds: Seedance 2.5.
• 15 seconds or less, no special need: try Seedance 2.0 first; it is cheaper.
• 15 seconds or less, you want the newest model for your own reasons: Seedance 2.5, and accept the extra cost per clip.
• Drafts: Mini or Fast at 480p.
• Anything else: read the catalog row and test.

A request that switches tier

Keep the id in a variable and switch by answer. This body works for every Seedance id that accepts the duration.

curl -X POST https://api.sume.com/v1/videos \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: tier-switch-001" \
  -d '{"model":"seedance-2","prompt":"A paper boat floats down a rain gutter, camera follows at water level, soft gray light","duration":10,"resolution":"720p","aspect_ratio":"16:9"}'

What the vendor says

ByteDance Seed lists Seedance 2.5's extension from 15 seconds to 30 seconds per generation and larger reference limits per pass than Sume's request validation allows (read 2026-10-05). Those are product claims for the vendor's own platforms; use the Sume catalog for what a Sume request can do. Read the model row with GET /v1/videos/models before you pin an id in code.

Whichever you pick, send a short test first. Prices and limits can change, and the catalog is the place a change shows up before your bill does. Keep the estimate function next to the model id so the two move together when you change tier.