AI Video Aspect Ratio and Resolution on VdoBloom: What to Pick Per Platform
9:16, 16:9, 4:5 or 21:9 — which VdoBloom models support each ratio, why image-to-video ignores your ratio picker, and the real credit cost of each resolution tier.
Pick 9:16 for TikTok, Reels and Shorts, 16:9 for YouTube and websites, 1:1 or 4:5 for feed posts, and 21:9 only when you genuinely want cinema bars — then choose the resolution tier second, because on VdoBloom resolution is what actually drives the credit cost, not the aspect ratio. A 5-second clip at 480p and the same clip at 1080p are identical in framing and four times apart in price.
The rule nobody tells you: image-to-video ignores your aspect ratio
This trips up more people than anything else on the platform. In VdoBloom’s model configuration, most image-to-video models are set with aspect-ratio control switched off — Kling 3.0 Omni image-to-video, Wan 2.6 and 2.7 image-to-video, Seedance 2 image-to-video, HappyHorse image-to-video, MiniMax H3 image-to-video and Kling 2.6 image-to-video all take their aspect ratio from the photo you upload. There is no ratio picker because there is nothing for it to do.
The practical consequence: if you want a 9:16 vertical clip from a photo, crop the photo to 9:16 before you upload it. Uploading a landscape photo and hoping the picker will save you produces a landscape video every time. Crop first in image editing, then animate.
Text-to-video is the opposite case: there is no input image, so the ratio picker is the only thing that decides the frame, and it matters a great deal which model you chose.
Which VdoBloom models support which ratios
| Model | Aspect ratios available | Resolution tiers | Durations |
|---|---|---|---|
| Seedance 2 (text-to-video) | 21:9, 16:9, 4:3, 1:1, 3:4, 9:16 | 480p, 720p, 1080p, 4K | 4–15s |
| Seedance 2.5 | 21:9, 16:9, 4:3, 1:1, 3:4, 9:16 | 480p, 720p, 1080p | 4–30s |
| Kling 3.0 Omni (text-to-video) | 16:9, 9:16, 1:1 | 720p, 1080p, 4K | 3–15s |
| Wan 3.0 | 16:9, 4:3, 1:1, 3:4, 9:16 | 480p, 720p, 1080p | 2–30s |
| HappyHorse 1.1 (text-to-video) | 16:9, 9:16, 1:1, 4:3, 3:4, 4:5, 5:4, 9:21, 21:9 | 720p, 1080p | 4–15s |
| Grok Imagine Video 1.5 | 1:1, 16:9, 9:16, 4:3, 3:4, 3:2, 2:3 | 480p, 720p, 1080p | 1–15s |
| Gemini Omni video | 16:9, 9:16 only | 720p, 1080p, 4K | 4, 6, 8 or 10s |
| LTX-2 Fast | 16:9, 9:16 only | 1080p, 1440p, 4K | 6, 8 or 10s |
| Veo 3.1 | 16:9, 9:16 only | Model default | Model default |
Two things fall straight out of that table. If you need 4:5 — the ratio that fills the most vertical space in an Instagram feed without being a Reel — HappyHorse 1.1 is one of very few video models on the platform that offers it natively. And if you want a square 1:1 clip, Veo 3.1 and the Gemini Omni video models cannot give you one; the platform filters 1:1 out of their picker entirely. Reach for Kling 3.0 Omni, Wan 3.0, Seedance or Grok instead.
What to use per platform
| Destination | Aspect ratio | Resolution to render | Note |
|---|---|---|---|
| TikTok, Reels, YouTube Shorts | 9:16 | 1080p | Vertical is non-negotiable; platform compression punishes soft sources hard |
| YouTube long-form | 16:9 | 1080p or 4K | 4K is worth it only if the rest of the video is 4K |
| Instagram feed post | 4:5 or 1:1 | 1080p | 4:5 occupies more screen; 1:1 is safer for cross-posting |
| Website hero or embed | 16:9 | 720p | 720p is plenty at typical embed widths and costs half |
| Paid social, test creative | 9:16 and 1:1 | 480p to test, 1080p to ship | Test motion cheaply, re-render the winner |
| Cinematic trailer | 21:9 | 1080p or 4K | Seedance and HappyHorse 1.1 only |
Resolution is the price lever, not the ratio
Changing 16:9 to 9:16 does not change what you pay. Changing 720p to 1080p roughly doubles it. Here are real VdoBloom credit costs for a 5-second clip, at $0.05 per credit (the Lite plan gives 300 credits for $15).
| Model and tier, 5 seconds | Credits | Cost | What you get |
|---|---|---|---|
| Wan 3.0, 480p | 16 | $0.80 | Draft only. Fine for checking motion |
| Wan 3.0, 720p | 32 | $1.60 | Good enough for embeds and stories |
| Wan 3.0, 1080p | 64 | $3.20 | Deliverable social video, best value 1080p |
| Kling 3.0 Omni, 720p | 40 | $2.00 | Native audio, strong human subjects |
| Kling 3.0 Omni, 1080p | 54 | $2.70 | The sweet spot for vertical people clips |
| Kling 3.0 Omni, 4K | 134 | $6.70 | Only when a 4K timeline demands it |
| Seedance 2.5, 720p | 100 | $5.00 | Complex camera moves and long takes |
| Seedance 2.5, 1080p | 180 | $9.00 | Hero shot |
| Seedance 2 text-to-video, 4K | 414 | $20.70 | Rarely justified. Render 1080p and upscale |
The honest advice in that last row: 4K text-to-video at 414 credits for five seconds is almost never the right call for social. Nothing you post to TikTok survives as 4K. Render 1080p and spend the difference on more variations.
A workflow that stops you re-rendering
- Decide the destination first. The ratio is a distribution decision, not a creative one.
- If starting from a photo, crop it to the target ratio before upload. Image-to-video inherits the photo’s frame.
- Draft at 480p or 720p. Confirm the motion, the timing and the framing.
- Re-render the winner at 1080p in the same ratio. Same prompt, same model, one tier up.
- Do not crop 16:9 down to 9:16 afterwards. You lose 68 percent of the pixels, and anything the model composed for the wide frame — faces near the edges especially — gets cut out.
That last point is the one that costs people the most. Cropping a landscape AI clip into a vertical one is not free re-framing; it is a heavy resolution loss on top of a composition the model never intended. Generating natively vertical on text-to-video or image-to-video costs the same credits and looks materially better.
Where the ratio picker lives
In the video creator, the aspect-ratio control appears under model settings and only lists the ratios your selected model actually supports — switch from Wan 3.0 to Veo 3.1 and the 1:1 option disappears. Per-model specs are listed on each model page, including Wan 3.0 and Seedance 2.5. Full credit tiers and plan costs are on the pricing page, and prompt structures that work well in vertical frames are collected in the Seedance prompt library.
Frequently asked questions
Does 9:16 cost more than 16:9?
No. Aspect ratio has no effect on credit cost anywhere in VdoBloom’s pricing. Only the resolution tier, the duration and the model change what you pay.
Why can I not choose an aspect ratio on image-to-video?
Because the output follows your uploaded image. Most image-to-video models on the platform have the aspect-ratio control switched off for exactly this reason. Crop the photo to the ratio you want before uploading.
Which model should I use for a 4:5 Instagram feed video?
HappyHorse 1.1 text-to-video and reference-to-video are the natural picks — they support 4:5 and 5:4 natively at 720p or 1080p. Otherwise render 1:1 and accept the smaller feed footprint rather than cropping down from 16:9.
Is 4K ever worth the credits?
For a 4K delivery timeline or a large-screen installation, yes. For social, no — a 5-second 4K Seedance 2 clip is 414 credits against 180 for 1080p on Seedance 2.5, and the platform you upload to will re-compress it anyway.
What resolution should I use for a website hero video?
720p at 16:9. At typical embed widths nobody can tell it from 1080p, it halves the credit cost, and the smaller file loads faster, which matters more to your visitors than the extra pixels.
Ready to try it?
Create your first AI video in minutes — no credit card required.
Start Creating Free →