Kakao Moment Video native ad: 720x1280 clip and thumbnail specs

A Kakao Moment Video native ad (VIDEO_NATIVE) takes a promotional video of at least 720x1280 (9:16), 1280x720 (16:9) or 1080x1080 (1:1), a custom thumbnail of the same size under 500 KB, and a 300x300 profile image. Kakao's creative page says the Video type was added with the update on September 28, 2026. For a vertical clip, ask Sume's Video Router for aspect_ratio: "9:16", then pull a still with video-frames for the thumbnail.

This post covers the files only. Targeting, bidding and the campaign setup stay in Kakao's ad tools.

What does Kakao ask for in a Video native creative?

The table copies the rows of the Video line from Kakao's creative-type list. Kakao writes every size as "or more", so the numbers are minimums, not exact targets.

Where do Kakao's own numbers disagree?

The size limit appears twice and differs. The creative-type list says 100 MB for the video. The parameter reference for creating a Display creative (videoFileUrl and videoFile) says 1 GB and lists AVI, FLV and MP4. I could not tell from the page which one the ad manager enforces, so plan for the smaller number and let the 1 GB figure be a margin.

The same reference caps the text fields: a title of 25 characters, a profile name of 20 and promotional text of 45. It also says the creative is created with videoFileUrl plus profileImageFileUrl, and the optional thumbnail goes in uploadThumbnailImageFileUrl for JSON requests. The page lists no clip length limit in the parts I read, so check that in the ad manager before you render a long cut.

How do you make the 9:16 clip with Sume?

Sume's Video Router lets you pin a catalog model. Its docs say seedance-2.5 accepts 4 to 30 seconds at 480p, 720p or 1080p, and the example request uses "aspect_ratio": "9:16" with a vertical UGC-style product clip prompt. Auto create controls default to 720p and 8 seconds, with 3 to 10 second clips at 16:9 or 9:16.

The docs do not state pixel dimensions per tier, so do not assume that 720p equals 720x1280. Read the returned file instead. A video-frames call at t = 0 returns frames[{t,url,width,height}] at source size, which gives you the clip's real width and height to compare with Kakao's 720x1280 minimum. If it comes back smaller, request the 1080p tier.

curl -X POST https://api.sume.com/v1/video-router/generate \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: kakao-moment-clip-001" \
  -d '{
    "model": "seedance-2.5",
    "prompt": "A vertical UGC-style product clip on a desk, natural light",
    "resolution": "1080p",
    "duration": 8,
    "aspect_ratio": "9:16",
    "mode": "async"
  }'

How do you get a thumbnail under 500 KB?

Use video frames on the finished clip: at takes 1 to 24 times in seconds, format is jpeg (default) or png, and max_edge clamps the long edge between 16 and 2160. Omit max_edge and the still keeps the source size. Submit always returns 202, so poll GET /v1/video-frames/:id until resource_status is ready.

Keep the long edge at 1280 or more for a 9:16 thumbnail, because Kakao's minimum is 720x1280. Sume's docs give no JPEG quality control for frames, so measure the file. If a still is over 500 KB, lower max_edge toward 1280 and try again, or re-encode it outside Sume. Pick a frame where the product is visible and sharp, since the thumbnail is what people see before the clip plays.

What to check before you upload

Four checks cover most rejections: the clip's real width and height, the file size against the 100 MB figure, the thumbnail under 500 KB at the same aspect ratio as the clip, and the three text lengths. Sume bills the video by the model's rate and video frames by its Modal compute, so a retry costs something; run the cheap checks first.