Seedance 2 5s clip: Runway API $1.80 flat vs Sume $0.88 to $1.89

Runway's API charges the same 36 credits per second for Seedance 2 at 480p and at 720p, so a 5-second clip is $1.80 either way. Seedance bills by video tokens, which grow with pixel count, so on a per-token seller the 480p clip is far cheaper: about $0.70 on fal's list and $0.88 on Sume, against $1.89 for 720p on Sume.

If you draft at 480p before spending on a final, the seller you pick changes your draft cost by more than half.

The token math

fal's pricing page lists Seedance 2 image-to-video and reference-to-video at $0.014 per 1000 tokens. Sume's pricing metadata reports the formula it uses for Seedance video: width x height x duration in seconds x 24 frames, divided by 1024, gives the token count. Sume then bills list x 1.25, which is $0.0175 per 1000 tokens for seedance-2.

For a 16:9 clip, Sume's size table is 864 x 496 at 480p and 1280 x 720 at 720p. Over five seconds that is 50,220 tokens at 480p and 108,000 tokens at 720p. At fal's $0.014 per 1000 tokens that is $0.70 and $1.51. Times 1.25, Sume's figures are $0.88 and $1.89. Runway's own Seedance 2 row is a flat 36 credits per second ($0.36) for both resolutions, which is $1.80 for five seconds.

Where each seller wins

At 720p Runway's flat rate is about 5 percent below Sume's, so if every clip is 720p the choice comes down to features, not price. At 480p the flat rate means you pay for pixels you did not render: Runway is more than double Sume's figure for a draft.

Aspect ratio shifts the token count too. A 9:16 clip is 496 x 864 at 480p, which is the same pixel count as 16:9, but a 1:1 clip is 640 x 640 and costs about 18 percent less at the same duration. Runway's per-second row does not change with shape.

A draft-then-final budget

Take ten 5-second drafts at 480p and two 5-second finals at 720p. On Sume that is 10 x $0.88 + 2 x $1.89 = $12.58. On Runway's API it is 12 x $1.80 = $21.60. If you also need 1080p finals, read the live pricing_skus and the size table for that resolution rather than extrapolating from these two rows.

Sume's documented range for seedance-2 is 4 to 15 seconds per clip, 480p to 1080p, so a 5-second draft is inside it. Runway's page also lists Seedance 2 fast and mini rows; this comparison keeps to the main model so the tokens line up.

Check the live number first

Two inputs here move: the provider's per-token list and Sume's margin. Pull GET /v1/videos/models for the current pricing_skus and use a dry-run estimate if your workspace offers one before a batch. The docs' example response in the video models page shows a sample value; treat the live endpoint as the source.