sedance.appOpen studio

Seedance 2.5

30 seconds in a single pass — no stitching, no seam to hide.

What is Seedance 2.5?

Seedance 2.5 generates 430 second video at up to 4k, with 40 image and 5 video references per request and native audio. It is available on the Creator plan and above, and through the API at /api/v1/generations. Typical wall-clock is 210s (p50) and 420s (p95).

ByteDance’s claim vs our measurement

The rows marked claimed below come from ByteDance’s own announcement and have not been independently confirmed against the provider API. No independent benchmarks for Seedance 2.5 existed when this page was written. We publish our own measurements as they land rather than restating a press release — see our benchmark page.

ByteDance’s claim vs our measurement

CapabilityByteDance’s claimOur measurement
Duration4–30s in 1s stepsconfirmed
Resolutions480p, 720p, 1080p, 4knot verified yet
Aspect ratios16:9, 9:16, 4:3, 3:4, 21:9, 1:1confirmed
Native audioYesnot verified yet
Total references50not verified yet
Image references40not verified yet
Video references5 (≤15s each)not verified yet
Audio references5not verified yet
End frameYesconfirmed
Return last frameYesconfirmed
Video extensionYesconfirmed
Region-level editingYesnot verified yet
R2V controlYesnot verified yet
3D camera blockoutYesnot verified yet
Multilingual dialogueYesnot verified yet

A row reads “not verified yet” when the figure comes from ByteDance’s announcement and we have not confirmed it against the provider API ourselves. We would rather show the gap than restate a keynote.

What it costs

Credit cost at 4k, standard tier. Derived from published vendor rates pending our own benchmark run.

00:00:04:004k16:9standard2,267cr≈ $22.67
00:00:17:004k16:9standard9,613cr≈ $96.13
00:00:30:004k16:9standard16,959cr≈ $169.59

The 30-second coherence test

One complex prompt — a character walking through three lighting environments with a wardrobe detail that must persist — run ten times at 30s/1080p, every take published unedited with the failure mode named where it drifts. It is the question every buyer actually has and nobody has answered publicly.

01

not run

02

not run

03

not run

04

not run

05

not run

06

not run

07

not run

08

not run

09

not run

10

not run

Not run yet — it needs provider access, and a fabricated score would defeat the entire point of the page. When it runs, this line carries the count that held end to end, the failure modes, the mean billed cost and the measured p50.

Call it from the API

curl https://sedance.app/api/v1/generations \
  -H "Authorization: Bearer $SEDANCE_API_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedance-2.5",
    "prompt": "A slow dolly-in across a rain-soaked rooftop at dusk",
    "resolution": "4k",
    "duration_sec": 30,
    "aspect_ratio": "16:9",
    "confirm_cost": true
  }'

Returns 202 with the job id and the credits held. Poll /api/v1/generations/:id — the poll cadence for a 30s job should start at 10s.

Questions

How long can a Seedance 2.5 video be?
4 to 30 seconds per request, in 1-second steps. That is a single continuous pass, not stitched clips.
Does Seedance 2.5 support 4K?
It outputs up to 4K. The 4K claim comes from ByteDance and is flagged as unverified on this page until we measure it ourselves.
How much does a 30-second Seedance 2.5 video cost?
16,959 credits at 4k, standard tier — about $169.59. The studio shows the exact figure before you generate and asks you to confirm anything over 800 credits.
Which plan includes Seedance 2.5?
The Creator plan and above. There is no free tier — every generation costs real GPU time, so access starts with a paid plan or a credit pack.
How many reference inputs does Seedance 2.5 accept?
Up to 50 in total: 40 images, 5 videos of at most 15s each, and 5 audio clips. The total is ByteDance’s announced figure; API exposure at GA is unconfirmed.

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