Reel and short video sizes: a clear guide
By Sure INSTANT team · Updated on Nov 11, 2026
A video filmed in one shape rarely suits every place you want to post it. A vertical frame fills a phone screen held upright, while a wide frame suits a screen turned on its side.
This guide lists the four sizes OneClip produces from a single upload, explains how the video is fitted into each new shape, and walks through the steps.
The four sizes OneClip produces
You upload the video once and choose the sizes you want. Each chosen size comes out as its own MP4 file.
| Shape | Size in pixels | Where it fits |
|---|---|---|
| Vertical 9:16 | 1080×1920 | Reels, TikTok, Shorts and Stories |
| Square 1:1 | 1080×1080 | Instagram and Facebook feed |
| Portrait 4:5 | 1080×1350 | A taller shape for the feed |
| Landscape 16:9 | 1920×1080 | YouTube |
Three ways to fit a video into a new shape
Changing the shape of a video always leaves a choice: keep everything and fill the empty space, or fill the frame and lose the edges.
- Blurred background: the whole video sits over a soft blurred copy of itself. Choose it when nothing in the picture may be cut.
- Crop to fill: the edges are cut from the centre so the picture fills the frame. Choose it when the subject stays in the middle.
- Coloured bars: the empty space takes a colour you choose. Choose it when you want your own colour around the video.
Sound and upload limits
OneClip accepts MP4, MOV, WebM and MKV files, up to 200 MB and 3 minutes. The sound is kept as it is, or removed with one switch when you plan to post without it.
How to resize a video with OneClip
- Upload your video once.
- Tick the sizes you need out of the four.
- Choose blurred background, crop to fill or coloured bars.
- Keep the sound or switch it off.
- Watch the preview: the first 6 seconds of every chosen size, smaller, watermarked and silent.
- Sign in to get each size as an MP4, plus all of them in one ZIP.
When there is no video yet: Instant Ads
OneClip reshapes a video you already have. Instant Ads builds a ready-to-publish ad from a store or page link, or from details you type, in lengths of 15, 30 or 60 seconds.
Instant Ads produces three of the same shapes: 16:9 at 1920×1080 for YouTube, 9:16 at 1080×1920 for Reels, TikTok, Shorts and Stories, and 1:1 at 1080×1080 for the Instagram and Facebook feed.