Seedance 2.0 vs Gen-4.5

Seedance 2.0 is the cheaper of the two at 72 credits per clip against Gen-4.5's 78 — a 6-credit gap on every generation. Seedance 2.0 returns a clip in ~80s / 5s clip against Gen-4.5's ~90s / 5s clip, which compounds quickly if you are iterating rather than finishing. Gen-4.5 produces the longer single clip at up to 20 seconds versus 12. Only Seedance 2.0 generates synchronized audio natively; the other outputs silent video. Pick Seedance 2.0 for drafts and volume, Gen-4.5 for the render you ship.

Updated September 3, 2026

ByteDance

Seedance 2.0

ByteDance's next-generation video model with a unified multimodal architecture. Generates high-quality video with synchronized audio from text, images, video clips, and audio inputs. Supports multimodal references (up to 9 images, 3 videos, 3 audio files), native audio generation, video editing, video extension, intelligent duration, and adaptive aspect ratio.

Credits
72
Turnaround
~80s / 5s clip
Max clip
12s
Native audioMultimodal referencesVideo extension
View Seedance 2.0 details

RunwayML

Gen-4.5

RunwayML's video generation model supporting both text-to-video and image-to-video with customizable duration, aspect ratio, and content moderation controls.

Credits
78
Turnaround
~90s / 5s clip
Max clip
20s
Text & image to videoCustomizableModeration controls
View Gen-4.5 details

Side-by-side specifications

SpecSeedance 2.0Gen-4.5
Credits per clip72 credits78 credits
Turnaround~80s / 5s clip~90s / 5s clip
Max clip length12s20s
Max resolution1080P1080P
Native audioYesNo
VendorByteDanceRunwayML

Pick Seedance 2.0 when…

  • You are generating in volume and the 6-credit difference per clip adds up fast
  • You are still exploring and need a tight generate-judge-regenerate loop (~80s / 5s clip versus ~90s / 5s clip)
  • The clip ships as-is and needs its own synchronized sound
  • The brief leans on native audio

Trade-off: You are capped at 12s per clip and will need extension or a cut for anything longer.

Pick Gen-4.5 when…

  • The clip is a final deliverable and 6 extra credits per render is not the constraint
  • You have settled on the shot and are rendering the version that ships
  • The shot cannot be cut — you need up to 20 seconds in one generation rather than 12
  • You are scoring the piece properly and would discard generated audio anyway
  • The brief leans on text & image to video

Trade-off: You pay 6 more credits on every generation; You wait 10s longer per clip; You will handle audio in post.

Vendor angle

These come from different vendors — ByteDance and RunwayML — which is where the interesting differences live. Vendors train on different data and optimise for different failure modes, so the same prompt can produce recognisably different motion, grain and lighting. On FlowAIVideo both sit behind one account and one balance, so you never have to pick a vendor before you have seen the output.

What it costs to decide

Running one clip on each costs 150 credits in total (72 + 78). A new account starts with 40 free credits, which covers Seedance 2.0 plus part of the other — enough to run a real comparison rather than reading about one. Paid plans start at 600 credits per month, and there is no per-model subscription: one balance, 22 models.

Test them on this prompt

Close-up of a barista pouring espresso, steam rising through a single shaft of window light, slow dolly in, 5 seconds

Fix the duration and aspect ratio, run both, and judge prompt adherence before aesthetics. A clip that looks good but shows the wrong thing is a failure.

Seedance 2.0 vs Gen-4.5 FAQ

Which is better, Seedance 2.0 or Gen-4.5?

Seedance 2.0 is the cheaper of the two at 72 credits per clip against Gen-4.5's 78 — a 6-credit gap on every generation. Seedance 2.0 returns a clip in ~80s / 5s clip against Gen-4.5's ~90s / 5s clip, which compounds quickly if you are iterating rather than finishing. Gen-4.5 produces the longer single clip at up to 20 seconds versus 12. Only Seedance 2.0 generates synchronized audio natively; the other outputs silent video. Pick Seedance 2.0 for drafts and volume, Gen-4.5 for the render you ship.

How much do Seedance 2.0 and Gen-4.5 cost?

Seedance 2.0 costs 72 credits per generation, and Gen-4.5 costs 78 credits per generation. Running one clip on each costs 150 credits in total (72 + 78). A new account starts with 40 free credits, which covers Seedance 2.0 plus part of the other — enough to run a real comparison rather than reading about one. Paid plans start at 600 credits per month, and there is no per-model subscription: one balance, 22 models.

Which is faster, Seedance 2.0 or Gen-4.5?

Seedance 2.0 typically returns a clip in ~80s / 5s clip, while Gen-4.5 takes ~90s / 5s clip. Unless you are running dozens of clips at once, either turnaround will feel quick in practice.

Which model makes longer clips, Seedance 2.0 or Gen-4.5?

Gen-4.5 produces the longer single clip at 20 seconds, against 12 seconds for the other.

Can I try Seedance 2.0 and Gen-4.5 on the same prompt?

Yes — that is the point of a shared credit balance. Send one prompt to both models at once and compare the clips side by side. Fix the prompt and the duration, and judge prompt adherence before aesthetics.

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